Forensic Entomology Distinction of bloodstains from fly artifacts: Difference between revisions
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| | Source: Forensic Science International 137 (2003) 152-159<br> | ||
Source: | |||
=<font color=orange>Distinction of bloodstain patterns from fly artifacts</font>= | |||
[More [[All Mark Benecke Publications|articles from MB]]] [Articles [http://wiki2.benecke.com/index.php?title=Media#Interviews_.26_Articles <font color=lightgrey>about MB</font>]]<br> | |||
'''BY MARK BENECKE <sup>1</sup> (corresponding author) and LARRY BARKSDALE <sup>2</sup>'''<br> | |||
<i><sup>1</sup> International Forensic Research & Consulting, Postfach 250411, 50520 Cologne, Germany, E-mail forensic@benecke.com <br> | |||
< | <sup>2</sup> Lincoln Police Department, 575 South 10th Street, Lincoln, Nebraska 68502, USA; lpd211@cjis.ci.lincoln.ne.us </i> | ||
50520 Cologne, Germany | |||
< | <html><a href="http://wiki2.benecke.com/images/5/55/Distinction_of_blood_stain_patterns_from_fly_artifacts_barksdale_benecke.pdf" target="_blank"><img src="http://wiki2.benecke.com/images/d/d7/Distinction_of_blood_stain_patterns_from_fly_artifacts_barksdale_benecke_preview.jpg" border="0" height="150" align="middle"><figcaption>Klick für's PDF!</figcaption></a></html> | ||
Nebraska 68502, USA; lpd211@cjis.ci.lincoln.ne.us< | |||
< | <font color=orange>Abstract/Summary</font><br> | ||
Forensic scientists may encounter blood spatter at a scene which may be | Forensic scientists may encounter blood spatter at a scene which may be | ||
pure or a mixture of fly artifacts and human bloodstains. It is | pure or a mixture of fly artifacts and human bloodstains. It is | ||
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advanced documentation of such stains since the mechanics of production | advanced documentation of such stains since the mechanics of production | ||
of fly artifacts are not determinable to the crime scene | of fly artifacts are not determinable to the crime scene | ||
reconstructionist from regular police forces. We describe three cases | reconstructionist from regular police forces.<br> | ||
in which experiments and crime scene reconstruction led to additional | |||
We describe three cases in which experiments and crime scene reconstruction led to additional | |||
information. Case 1: Above the position of a victim, numerous blood | information. Case 1: Above the position of a victim, numerous blood | ||
stains of the low-high velocity type were found. Exclusion of these | stains of the low-high velocity type were found. Exclusion of these | ||
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submillimeter stains were found on a lamp between the two corpses. | submillimeter stains were found on a lamp between the two corpses. | ||
Activity of flies was less likely compared to alternative scenario of | Activity of flies was less likely compared to alternative scenario of | ||
moving lampshade and violent stabbing. <br> | moving lampshade and violent stabbing.<br> | ||
< | |||
<font color=orange>Key Words</font><br> | |||
Blow Flies, Forensic Entomology, Blood Stain Pattern Interpretation, | |||
Blood Spatter Artifacts<br> | Blow Flies, Forensic Entomology, Blood Stain Pattern Interpretation, Blood Spatter Artifacts<br> | ||
<font color=orange>1. Introduction</font><br> | |||
In the last years, forensic entomology [1-7] and blood stain pattern | In the last years, forensic entomology [1-7] and blood stain pattern | ||
analysis [8-19] became more and more part of forensic investigations | analysis [8-19] became more and more part of forensic investigations | ||
and trials [14] outside of the United States. <br> | and trials [14] outside of the United States. <br> | ||
In this context, crime scene experts often note that flies might leave | In this context, crime scene experts often note that flies might leave | ||
information that could produce confusion within the scene. The | information that could produce confusion within the scene. The | ||
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regurgitation and defecation from a fly are frequently not taken into | regurgitation and defecation from a fly are frequently not taken into | ||
account. <br> | account. <br> | ||
Only old German texts [8] and modern text books from the United States | Only old German texts [8] and modern text books from the United States | ||
mention artifacts produced by flies [16-19], e.g.: <br> | mention artifacts produced by flies [16-19], e.g.: <br> | ||
"The activity of flies at the scene where blood has been shed is | "The activity of flies at the scene where blood has been shed is | ||
another possible source of small stains of blood that may be confused | another possible source of small stains of blood that may be confused | ||
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surface to allow enzymes to break down the blood. At a later time, the | surface to allow enzymes to break down the blood. At a later time, the | ||
flies return to the areas of regurgitated blood and consume a portion | flies return to the areas of regurgitated blood and consume a portion | ||
of the blood. The surfaces upon which these activities have taken place | of the blood.<br> | ||
The surfaces upon which these activities have taken place | |||
will contain small spots of blood material which are often a millimeter | will contain small spots of blood material which are often a millimeter | ||
or less in diameter with no definite point of convergence or origin. | or less in diameter with no definite point of convergence or origin. | ||
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locations may be inconsistent with blood spatter associated with | locations may be inconsistent with blood spatter associated with | ||
injuries sustained by the victim." [19]<br> | injuries sustained by the victim." [19]<br> | ||
Although not true spatter, another pattern often confused with spatter | Although not true spatter, another pattern often confused with spatter | ||
is the "fly speck" or "fly spot" pattern. Flies present within the | is the "fly speck" or "fly spot" pattern. Flies present within the | ||
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examination.<br> | examination.<br> | ||
In the case of regurgitation, the specks are remarkably | In the case of regurgitation, the specks are remarkably | ||
symmetrical....Most often, the analyst finds these patterns in warm | symmetrical....Most often, the analyst finds these patterns in warm | ||
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blood with a presumptive test. Obviously, care should be exercised in | blood with a presumptive test. Obviously, care should be exercised in | ||
evaluating any abnormal patterns which meet these criteria." [10]<br> | evaluating any abnormal patterns which meet these criteria." [10]<br> | ||
However, no integrated approach by natural sciences and criminalists | However, no integrated approach by natural sciences and criminalists | ||
had been used until actual case work (see cases below) and presentation | had been used until actual case work (see cases below) and presentation | ||
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between blood spatter caused by force and blood spatter-like patterns | between blood spatter caused by force and blood spatter-like patterns | ||
produced by flies.<br> | produced by flies.<br> | ||
This is expecially important since even artifacts caused by flies may | This is expecially important since even artifacts caused by flies may | ||
very well include the vicitim´s blood. Neither presumptive blood | very well include the vicitim´s blood. Neither presumptive blood | ||
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following text illustrates stains produced by the activity of flies and | following text illustrates stains produced by the activity of flies and | ||
suggests methodology for evaluating stains in a decomposed body scene.<br> | suggests methodology for evaluating stains in a decomposed body scene.<br> | ||
Furthermore, from the above quotes it appears that some documentation | Furthermore, from the above quotes it appears that some documentation | ||
of the crate was possible. In many countries, it is however unlikely | of the crate was possible. In many countries, it is however unlikely | ||
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therefore, documentation of crates has, to our knowledge and does | therefore, documentation of crates has, to our knowledge and does | ||
usually never take place. <br> | usually never take place. <br> | ||
< | |||
<font color=orange>2. Blood Spatter Types</font><br> | |||
Blood that is subjected to a low velocity impact (less than 1.5 m x | Blood that is subjected to a low velocity impact (less than 1.5 m x | ||
s-1); resulting blood spots often around 4-8 mm in diameter) is called | s-1); resulting blood spots often around 4-8 mm in diameter) is called | ||
low velocity blood spatter. It is caused by free-falling blood under | low velocity blood spatter. It is caused by free-falling blood under | ||
the influence of gravity, including blood cast off from fist shoe, or | the influence of gravity, including blood cast off from fist shoe, or | ||
weapon. <br> | weapon.<br> | ||
Blood spatter as reported in the following three cases was usually | Blood spatter as reported in the following three cases was usually | ||
thought to be caused be either high velocity impact, or by a mixture of | thought to be caused be either high velocity impact, or by a mixture of | ||
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to a high velocity impact (>7.5 m x s-1), e.g. a gunshot (blood | to a high velocity impact (>7.5 m x s-1), e.g. a gunshot (blood | ||
spots typically < 1 mm in diameter) [9]. <br> | spots typically < 1 mm in diameter) [9]. <br> | ||
<br> | |||
<font color=orange>3. Case I: Double homicide in Nebraska</font><br> | |||
<font color=orange>3.1. General Scenario</font><br> | |||
The remains of two men were discovered at 14:25 hrs on 14. June 1997 in | The remains of two men were discovered at 14:25 hrs on 14. June 1997 in | ||
in a third level apartment in a five-plex apartment building in urban | in a third level apartment in a five-plex apartment building in urban | ||
Lincoln, Nebraska, USA [23]. <br> | Lincoln, Nebraska, USA [23]. <br> | ||
Both victims were fully clothed; both had a gunshot wound to the head | Both victims were fully clothed; both had a gunshot wound to the head | ||
and gunshot wounds to the torso. One victim was found face down in the | and gunshot wounds to the torso. One victim was found face down in the | ||
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carpeting. Pools of a reddish substance were observed around the bodies | carpeting. Pools of a reddish substance were observed around the bodies | ||
of the victims.<br> | of the victims.<br> | ||
The bodies were in the active decay stage with black putrefaction only | The bodies were in the active decay stage with black putrefaction only | ||
just beginning; the skin was intact everywhere except where there were | just beginning; the skin was intact everywhere except where there were | ||
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well as some adult flies were present. The temperature registered 30 | well as some adult flies were present. The temperature registered 30 | ||
°C on the wall thermostat.<br> | °C on the wall thermostat.<br> | ||
< | |||
<font color=orange>3.2. Forensic Entomology</font><br> | |||
On 15. June 1997, at 06:45 hrs, the police collected six adult flies, | On 15. June 1997, at 06:45 hrs, the police collected six adult flies, | ||
three third instar fly larvae and several hundred first instar fly | three third instar fly larvae and several hundred first instar fly | ||
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that two distinctly separate periods of egg-laying by adult flies had | that two distinctly separate periods of egg-laying by adult flies had | ||
taken place. <br> | taken place. <br> | ||
< | |||
<font color=orange>3.3. Blood Stains</font><br> | |||
Initial observation of the scene gave the appearance of extensive low, | Initial observation of the scene gave the appearance of extensive low, | ||
medium and high velocity blood spatters. Above the position of one of | medium and high velocity blood spatters. Above the position of one of | ||
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and the walls around the victims. The stains were tested positive for | and the walls around the victims. The stains were tested positive for | ||
blood with a quick test for hemoglobin (Hemastix/Heglostix)<br> | blood with a quick test for hemoglobin (Hemastix/Heglostix)<br> | ||
The first assumption to be made was that there had been slinging of a | The first assumption to be made was that there had been slinging of a | ||
lot of blood around the kitchen and living room. This would suggest not | lot of blood around the kitchen and living room. This would suggest not | ||
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bathroom of an assaultive nature and the bloodshed had taken place in | bathroom of an assaultive nature and the bloodshed had taken place in | ||
the kitchen and living room.<br> | the kitchen and living room.<br> | ||
Recostructing the angle of impact of many of those stains, however, led | Recostructing the angle of impact of many of those stains, however, led | ||
nowhere. There was no indication that the bodies had been moved and | nowhere. There was no indication that the bodies had been moved and | ||
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(b) transferred to the walls? <br> | (b) transferred to the walls? <br> | ||
< | <font color=orange>3.4. Experiments and Measurements at the Scene of Crime</font><br> | ||
It is known that after feeding, flies regurgitate and defecate. Hence, | It is known that after feeding, flies regurgitate and defecate. Hence, | ||
flies could have caused stains, containing blood of the victims, by | flies could have caused stains, containing blood of the victims, by | ||
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teardrop-like stains was found to be highly suspicious for fly activity | teardrop-like stains was found to be highly suspicious for fly activity | ||
(fig. 3 b). <br> | (fig. 3 b). <br> | ||
Additional tests under laboratory conditions on vertical paper surfaces | Additional tests under laboratory conditions on vertical paper surfaces | ||
with adult Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae) | with adult Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae) | ||
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and supplied with a reddish-brown food mixture, let to the following | and supplied with a reddish-brown food mixture, let to the following | ||
results: <br> | results: <br> | ||
• After one day in a breedings cage, of 304 stains, | • After one day in a breedings cage, of 304 stains, | ||
112 (36.8 %) had a round shape whereas 192 (63.2%) had a tear- or | 112 (36.8 %) had a round shape whereas 192 (63.2%) had a tear- or | ||
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left, 19.8% upwards right; 19.3% downwards left; 18.2% downwards right. | left, 19.8% upwards right; 19.3% downwards left; 18.2% downwards right. | ||
<br> | <br> | ||
• The ratio Ltl/Lb was 1.5 ± 1.6 (n = | • The ratio Ltl/Lb was 1.5 ± 1.6 (n = | ||
80) (i.e., tendency towards ratios >1). <br> | 80) (i.e., tendency towards ratios >1). <br> | ||
However, single stains will not provide results that are statistically | However, single stains will not provide results that are statistically | ||
sound. Although the ratio does not conclusively identify a stain as a | sound. Although the ratio does not conclusively identify a stain as a | ||
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5.).<br> | 5.).<br> | ||
< | <font color=orange>3.5. Conclusion</font><br> | ||
With information that stains appearing as human blood spatters were fly | With information that stains appearing as human blood spatters were fly | ||
artifacts, coupled with other scene evidence, we felt confident that | artifacts, coupled with other scene evidence, we felt confident that | ||
the possibility of an execution or revenge slaying could be put into | the possibility of an execution or revenge slaying could be put into | ||
the mix of suspect behaviors at our crime scene.<br> | the mix of suspect behaviors at our crime scene.<br> | ||
< | |||
<font color=orange>4. Case II: Corpse of Lonely Woman</font><br> | |||
In Summer 2001, a dead female person was found in her bedroom in an | In Summer 2001, a dead female person was found in her bedroom in an | ||
urban appartment in Cologne, Germany. The body had entered dried-out | urban appartment in Cologne, Germany. The body had entered dried-out | ||
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blow flies had been present, or if those dots had to be attributed to a | blow flies had been present, or if those dots had to be attributed to a | ||
source to be investigated on. <br> | source to be investigated on. <br> | ||
The windows were closed before the police entered which explained the | The windows were closed before the police entered which explained the | ||
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very clean and expensively furnished. The bathtub was half filled with | very clean and expensively furnished. The bathtub was half filled with | ||
discolorated water that was most likely used to wash clothing. <br> | discolorated water that was most likely used to wash clothing. <br> | ||
Since the entrance door was regularly locked and no signs of a violent | Since the entrance door was regularly locked and no signs of a violent | ||
fight were present, a reddish spatter field at a fan chain in the | fight were present, a reddish spatter field at a fan chain in the | ||
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piece of paper. <br> | piece of paper. <br> | ||
Because of the nature of the stains, they were neither taken into | Because of the nature of the stains, they were neither taken into | ||
account for the further police investigation nor the reconstruction of | account for the further police investigation nor the reconstruction of | ||
the events at the scene. The case was considered to be self neglect in | the events at the scene. The case was considered to be self neglect in | ||
contrast to killing, or neglect by another person. <br> | contrast to killing, or neglect by another person. <br> | ||
< | |||
<font color=orange>5. Case III: Slaying of mother and child</font><br> | |||
On 30. January 2001, the dead bodies of a mother and her child were | On 30. January 2001, the dead bodies of a mother and her child were | ||
found in the living room of their house on the border of the city of | found in the living room of their house on the border of the city of | ||
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child that had been sleeping upstairs was alive and not hurt. Blood | child that had been sleeping upstairs was alive and not hurt. Blood | ||
stain patterns were used to determine the course of events. <br> | stain patterns were used to determine the course of events. <br> | ||
The crime scene reconstruction based on blood spatter became important | The crime scene reconstruction based on blood spatter became important | ||
to check the statements of an accused man who owned a knife that was | to check the statements of an accused man who owned a knife that was | ||
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medico-legal considerations, it was thought that the velocity of the | medico-legal considerations, it was thought that the velocity of the | ||
blood spatter might help to address theses questions. <br> | blood spatter might help to address theses questions. <br> | ||
Amongst numerous other reddish stains in the house (in this case, due | Amongst numerous other reddish stains in the house (in this case, due | ||
to a local police procedure, all stains determined as originating from | to a local police procedure, all stains determined as originating from | ||
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asked for by the police and later again requested by the judge during | asked for by the police and later again requested by the judge during | ||
the trial.<br> | the trial.<br> | ||
The tiny, round stains on the lamp were distributed over the complete | The tiny, round stains on the lamp were distributed over the complete | ||
surface (fig. 3). Genetic fingerprinting led to one conclusive DNA type | surface (fig. 3). Genetic fingerprinting led to one conclusive DNA type | ||
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initial velocity but got slowed down due to the resistance of the air. <br> | initial velocity but got slowed down due to the resistance of the air. <br> | ||
On the other hand, since a possible patterning as in fly artifacts | On the other hand, since a possible patterning as in fly artifacts | ||
could could not be ruled out with certainty (fig. 3d), no absolute | could could not be ruled out with certainty (fig. 3d), no absolute | ||
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fighting, inside of the room during the crime.<br> | fighting, inside of the room during the crime.<br> | ||
< | <font color=orange>6. Practical hints</font><br> | ||
From our case work experience and from our experiments, the following | From our case work experience and from our experiments, the following | ||
suggestions and techniques are offered for use in differentiating | suggestions and techniques are offered for use in differentiating | ||
between fly artifacts and human bloodstain patterns (fig. 4).<br> | between fly artifacts and human bloodstain patterns (fig. 4).<br> | ||
1. Document fly activity at a scene. Flies will be at a scene if access | 1. Document fly activity at a scene. Flies will be at a scene if access | ||
to the scene is available to them. They will stay at the scene as long | to the scene is available to them. They will stay at the scene as long | ||
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Follow standard protocols of description of insects at crimes scenes | Follow standard protocols of description of insects at crimes scenes | ||
[2,3,22] – where, when, how many?<br> | [2,3,22] – where, when, how many?<br> | ||
2. Document the range of stains. Fly activity will often | 2. Document the range of stains. Fly activity will often | ||
concentrate near light sources, on light colored walls, windows and | concentrate near light sources, on light colored walls, windows and | ||
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Compare stains away from the body with stains near the body.<br> | Compare stains away from the body with stains near the body.<br> | ||
3. Compare stains with known fly artifact patterns.<br> | 3. Compare stains with known fly artifact patterns.<br> | ||
4. Identify suspected human bloodstain patterns that are of the "spot" | 4. Identify suspected human bloodstain patterns that are of the "spot" | ||
or "tear" drop pattern that offer a potential for use in reconstruction | or "tear" drop pattern that offer a potential for use in reconstruction | ||
and eliminate the following:<br> | and eliminate the following:<br> | ||
a. Stains that have a tail/body (Ltl/Lb) ratio greater than one,<br> | a. Stains that have a tail/body (Ltl/Lb) ratio greater than one,<br> | ||
b. Stains with a tadpole/sperm type structure, <br> | b. Stains with a tadpole/sperm type structure, <br> | ||
c. Stains with a sperm cell type structure that do not end in a small | |||
dot, <br> | c. Stains with a sperm cell type structure that do not end in a small dot,<br> | ||
d. Any stains without a distinguishable tail and body, <br> | d. Any stains without a distinguishable tail and body, <br> | ||
e. Any stains with a wavy and irregular linear structure, <br> | e. Any stains with a wavy and irregular linear structure, <br> | ||
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Cast off human blood will produce stains, within a group, that | Cast off human blood will produce stains, within a group, that | ||
indicates a common general convergence point.<br> | indicates a common general convergence point.<br> | ||
5. Note the absence of known human bloodstain pattern | 5. Note the absence of known human bloodstain pattern | ||
characteristics. The absence of misting around a concentrated mass | characteristics. The absence of misting around a concentrated mass | ||
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Within a group, human cast off patterns often leave secondary wave cast | Within a group, human cast off patterns often leave secondary wave cast | ||
off patterns and run off patterns.<br> | off patterns and run off patterns.<br> | ||
6. Cover blood stains, especially on the floor, with paper sheets to | 6. Cover blood stains, especially on the floor, with paper sheets to | ||
prevent them being destroyed by investigators walking on the stains. <br> | prevent them being destroyed by investigators walking on the stains. <br> | ||
7. One or two stains do not make a case. Stains that could be fly | 7. One or two stains do not make a case. Stains that could be fly | ||
artifacts should be eliminated and an evaluation based upon stains that | artifacts should be eliminated and an evaluation based upon stains that | ||
can be explained in terms of origin and relevance to the | can be explained in terms of origin and relevance to the | ||
reconstruction. <br> | reconstruction. <br> | ||
8. Use a high resolution camera with a macro lens and include a scale | 8. Use a high resolution camera with a macro lens and include a scale | ||
in every single picture.<br> | in every single picture.<br> | ||
Forensic scientists, crime scene technicians and investigators may | Forensic scientists, crime scene technicians and investigators may | ||
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an informed identification, or at least advanced documentation of such | an informed identification, or at least advanced documentation of such | ||
stains. <br> | stains. <br> | ||
< | |||
<font color=orange>Acknowledgements</font><br> | |||
Dr. Brett Ratcliffe, University of Nebraska (Lincoln), performed the | Dr. Brett Ratcliffe, University of Nebraska (Lincoln), performed the | ||
species determination of the flies and kindly agreed that his findings | species determination of the flies and kindly agreed that his findings | ||
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crimes scenes for case work as well as research purposes. The reviewers | crimes scenes for case work as well as research purposes. The reviewers | ||
provided us with excellent comments.<br> | provided us with excellent comments.<br> | ||
< | |||
<font color=orange>References</font><br> | |||
[1] K.G.V. Smith, Kenneth, A Manual of Forensic | [1] K.G.V. Smith, Kenneth, A Manual of Forensic | ||
Entomology, London: Trustees of the British Museum (Natural History), | Entomology, London: Trustees of the British Museum (Natural History), | ||
Line 446: | Line 481: | ||
The Utility of Arthropods in Legal Investigations, Boca Raton: CRC | The Utility of Arthropods in Legal Investigations, Boca Raton: CRC | ||
Press, 2001.<br> | Press, 2001.<br> | ||
[3] E. P. Catts, N. H. Haskell (Eds.), Entomology and | [3] E. P. Catts, N. H. Haskell (Eds.), Entomology and | ||
Death, A Procedural Guide, Clemson, South Carolina: Joyce's Print Shop, | Death, A Procedural Guide, Clemson, South Carolina: Joyce's Print Shop, | ||
1990.<br> | 1990.<br> | ||
[4] Z. Erzinclioglu, [[Maggots, Murder and Men]]: | [4] Z. Erzinclioglu, [[Maggots, Murder and Men]]: | ||
Memories and Reflections of a Forensic Entomologist, Great Horkesley | Memories and Reflections of a Forensic Entomologist, Great Horkesley | ||
(Colchester): Harley Books, 2000.<br> | (Colchester): Harley Books, 2000.<br> | ||
[5] M. L. Goff | [5] M. L. Goff: A Fly for the Prosecution: How insect Evidence Helps Solve Crimes, London, Cambridge: Harvard University Press, 2000.<br> | ||
Evidence Helps Solve Crimes, London, Cambridge: Harvard University | |||
Press, 2000.<br> | |||
[6] B. Greenberg, J. C. Kunich, Entomology and the | [6] B. Greenberg, J. C. Kunich, Entomology and the | ||
Law: Flies as Forensic Indicators, Oxford: Cambridge University Press, | Law: Flies as Forensic Indicators, Oxford: Cambridge University Press, | ||
2002.<br> | 2002.<br> | ||
[7] M. Benecke, B. Seifert | |||
am Beispiel eines Tötungsdeliktes | [7] M. Benecke, B. Seifert: Forensische Entomologie am Beispiel eines Tötungsdeliktes. Eine kombinierte Spuren- und Liegezeitanalyse (Forensic Entomology in a high profile murder case, A combined analysis of stains and post mortem interval), Archiv für Kriminologie 204 (1999) 52-60.<br> | ||
[8] E. Piotrowski, Ueber Entstehung, Form, Richtung und Ausbreitung der Blutspuren nach Hiebwunden des Kopfes (About Causes, form, directionality and distribution of blood stains after beating of the head), Wien, März, 1895.<br> | [8] E. Piotrowski, Ueber Entstehung, Form, Richtung und Ausbreitung der Blutspuren nach Hiebwunden des Kopfes (About Causes, form, directionality and distribution of blood stains after beating of the head), Wien, März, 1895.<br> | ||
[9] H. L. MacDonell, Bloodstain Patterns, Corning, New York, Laboratory of Forensic Science, 1995.<br> | [9] H. L. MacDonell, Bloodstain Patterns, Corning, New York, Laboratory of Forensic Science, 1995.<br> | ||
[10] T. Bevel, R.M. Gardner, Bloodstain pattern analysis, with an Introduction to Crime Scene Reconstruction. New York, | [10] T. Bevel, R.M. Gardner, Bloodstain pattern analysis, with an Introduction to Crime Scene Reconstruction. New York, | ||
CRC Press, 1997. <br> | CRC Press, 1997. <br> | ||
[11] S.H. James, W.G. Eckert (Eds.), Interpretation of Bloodstain Evidence at Crime Scenes, 2nd ed., CRC Press, Boca Raton, | [11] S.H. James, W.G. Eckert (Eds.), Interpretation of Bloodstain Evidence at Crime Scenes, 2nd ed., CRC Press, Boca Raton, | ||
1998.<br> | 1998.<br> | ||
[12] J.L. Bunker, Blood Stain Evidence Manual, Vol. 3, Identification of Stain and Pattern Characteristics. Doje's Press, | [12] J.L. Bunker, Blood Stain Evidence Manual, Vol. 3, Identification of Stain and Pattern Characteristics. Doje's Press, | ||
Ococee (Florida), 1998.<br> | Ococee (Florida), 1998.<br> | ||
[13] S.H. James (Ed.), Scientific and Legal Applications of Bloodstain Pattern Interpretation, Boca Raton, CRC | [13] S.H. James (Ed.), Scientific and Legal Applications of Bloodstain Pattern Interpretation, Boca Raton, CRC | ||
Press, 1999. <br> | Press, 1999. <br> | ||
[14] Ristenbatt RR, III, Shaler RC A Bloodstain Pattern Interpretation in a Homicide Case Involving an Apparent ‘Stomping’. J Forensic Sci 40 (1995) 139-145.<br> | [14] Ristenbatt RR, III, Shaler RC A Bloodstain Pattern Interpretation in a Homicide Case Involving an Apparent ‘Stomping’. J Forensic Sci 40 (1995) 139-145.<br> | ||
[15] J. B. Lassaigne, Neue Untersuchung zur Erkennung von Blutflecken auf Eisen und Stahl (New Investigation into blood stains on iron and steel), Vierteljahresschrift für gerichtliche | [15] J. B. Lassaigne, Neue Untersuchung zur Erkennung von Blutflecken auf Eisen und Stahl (New Investigation into blood stains on iron and steel), Vierteljahresschrift für gerichtliche | ||
und oeffentliche Medicin 10 (1856) 285-289. <br> | und oeffentliche Medicin 10 (1856) 285-289. <br> | ||
[16] T.W. Adair, False Wave Cast-Off: Considering the Mechanism of Stain Formation, International Association of Bloodstain | [16] T.W. Adair, False Wave Cast-Off: Considering the Mechanism of Stain Formation, International Association of Bloodstain | ||
Pattern Analysts News 14(1) (1998) 2.<br> | Pattern Analysts News 14(1) (1998) 2.<br> | ||
[17] R. E. Brown, R. I. Hawkes, M. A. Parker, J. H. Byrd, Entomological Alteration of Bloodstain Evidence, in: J.H. Byrd, J.L. Castner (Eds.) Entomological Evidence: The Utility of Arthropods | [17] R. E. Brown, R. I. Hawkes, M. A. Parker, J. H. Byrd, Entomological Alteration of Bloodstain Evidence, in: J.H. Byrd, J.L. Castner (Eds.) Entomological Evidence: The Utility of Arthropods | ||
in Legal Investigations, Boca Raton, CRC Press, 2000.<br> | in Legal Investigations, Boca Raton, CRC Press, 2000.<br> | ||
Line 485: | Line 527: | ||
[18] T. Bevel, R.M. Gardener, Fly Spots, in: T. Bevel, R.M. Gardner, Bloodstain pattern analysis, with an Introduction | [18] T. Bevel, R.M. Gardener, Fly Spots, in: T. Bevel, R.M. Gardner, Bloodstain pattern analysis, with an Introduction | ||
to Crime Scene Reconstruction, New York, CRC Press, 1997, p. 166-167.<br> | to Crime Scene Reconstruction, New York, CRC Press, 1997, p. 166-167.<br> | ||
[19] S.H. James, T. P. Sutton, Medium- and High-Velocity Impact Blood Spatter, in: S.H. James, W. G. Eckert (Eds.), Interpretation of Bloodstain Evidence at Crime Scenes, 2nd ed., | [19] S.H. James, T. P. Sutton, Medium- and High-Velocity Impact Blood Spatter, in: S.H. James, W. G. Eckert (Eds.), Interpretation of Bloodstain Evidence at Crime Scenes, 2nd ed., | ||
CRC Press, Boca Raton, New York, CRC Press, 1998, pp. 59-83.<br> | CRC Press, Boca Raton, New York, CRC Press, 1998, pp. 59-83.<br> | ||
[20] B.C. Ratcliffe, Forensic Entomology Case Study, Final Report, In: Case File 97-063436 (Lincoln Police | [20] B.C. Ratcliffe, Forensic Entomology Case Study, Final Report, In: Case File 97-063436 (Lincoln Police | ||
Department)/A97-102/103 (Pathology Medical Services, P.C.), 8. July 1997.<br> | Department)/A97-102/103 (Pathology Medical Services, P.C.), 8. July 1997.<br> | ||
[21] M. Benecke | |||
Considerations, Meeting of the European Association of Forensic Entomologist, Frankfurt, 2.-5. April 2003, p. 29-30. <br> | [21] M. Benecke: Cases and Considerations, Meeting of the European Association of Forensic Entomologist, Frankfurt, 2.-5. April 2003, p. 29-30. <br> | ||
[22] S.H. James, The Documentation, Collection and Evaluation of Bloodstain Evidence, in: S.H. James, W. G. Eckert | [22] S.H. James, The Documentation, Collection and Evaluation of Bloodstain Evidence, in: S.H. James, W. G. Eckert | ||
(Eds.), Interpretation of Bloodstain Evidence at Crime Scenes, 2nd ed., CRC Press, Boca Raton, 1998, p. 125-152. <br> | (Eds.), Interpretation of Bloodstain Evidence at Crime Scenes, 2nd ed., CRC Press, Boca Raton, 1998, p. 125-152. <br> | ||
<br> | [23] M. Benecke, M, L. Barksdale, J. Sundermeier, S. Reibe, B.C. Ratcliffe: Blood spatter artifacts caused by flies and determination of post mortem inverval (PMI) by use of blowfly maggots. Zoology, Analysis of Complex Systems (formerly Zoologische Jahrbücher) 103 Suppl. III (2000) 106. | ||
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* [[2008 11 Archiv fuer Kriminologie: Leichen Entsorgung in einer Biotonne|Leichen-"Entsorgung" in einer Biotonne]] <font size="-2" color="#FF0000" face="helvetica">GERMAN TEXT</font><br> | |||
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* [[2014 Projektarbeit Forensische Entomologie Berechnung der Liegezeit mit Hilfe von Maden|Berechnung der Liegezeit mit Hilfe von Maden]] <font size="-2" color="#FF0000" face="helvetica">GERMAN TEXT</font><br> | |||
* [[2019-01 Die Welt: An seine erste Leiche kann er sich nicht mehr erinnern |An seine erste Leiche kann er sich nicht mehr erinnern]] <font size="-2" color="#FF0000" face="helvetica">GERMAN TEXT</font><br> | |||
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* [[2017 06 AAFE Treviso|A Forensic Entomological case of neglect of an elderly man in Calabria, Southern Italy]]<br> | |||
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Latest revision as of 10:06, 4 March 2019
Source: Forensic Science International 137 (2003) 152-159
Distinction of bloodstain patterns from fly artifacts
[More articles from MB] [Articles about MB]
BY MARK BENECKE 1 (corresponding author) and LARRY BARKSDALE 2
1 International Forensic Research & Consulting, Postfach 250411, 50520 Cologne, Germany, E-mail forensic@benecke.com
2 Lincoln Police Department, 575 South 10th Street, Lincoln, Nebraska 68502, USA; lpd211@cjis.ci.lincoln.ne.us
Abstract/Summary
Forensic scientists may encounter blood spatter at a scene which may be
pure or a mixture of fly artifacts and human bloodstains. It is
important to be able to make an informed identification, or at least
advanced documentation of such stains since the mechanics of production
of fly artifacts are not determinable to the crime scene
reconstructionist from regular police forces.
We describe three cases in which experiments and crime scene reconstruction led to additional
information. Case 1: Above the position of a victim, numerous blood
stains of the low-high velocity type were found. Exclusion of these
stains being caused by force (but instead caused by the activity of
adult blow flies) by use of the following observations that were
confirmed in experiments: a) Sperm-/tadpole-like structure with length
> width, b) random directionality c) mixture of round symmetrical
and teardrop shaped stains. Case 2: A reddish spatter field was found
on a fan chain two rooms away from the place where a dead woman was
found. Localization of the spatter on the bottom end of the surface
hinted strongly towards fly activity. Case 3: Double homicide;
submillimeter stains were found on a lamp between the two corpses.
Activity of flies was less likely compared to alternative scenario of
moving lampshade and violent stabbing.
Key Words
Blow Flies, Forensic Entomology, Blood Stain Pattern Interpretation, Blood Spatter Artifacts
1. Introduction
In the last years, forensic entomology [1-7] and blood stain pattern
analysis [8-19] became more and more part of forensic investigations
and trials [14] outside of the United States.
In this context, crime scene experts often note that flies might leave
information that could produce confusion within the scene. The
mechanics of production of fly artifacts are not determinable to the
crime scene reconstructionist from regular police forces, since
regurgitation and defecation from a fly are frequently not taken into
account.
Only old German texts [8] and modern text books from the United States
mention artifacts produced by flies [16-19], e.g.:
"The activity of flies at the scene where blood has been shed is
another possible source of small stains of blood that may be confused
with medium- to high-velocity impact spatter... An understanding of the
mechanics of flies feeding on blood an decomposing bodies is essential
for proper interpretation of these bloodstains. The horse fly is
characterized as a biter, while the common house fly is specialized as
a lapper and sucker. Flies ingest blood and regurgitate it onto a
surface to allow enzymes to break down the blood. At a later time, the
flies return to the areas of regurgitated blood and consume a portion
of the blood.
The surfaces upon which these activities have taken place
will contain small spots of blood material which are often a millimeter
or less in diameter with no definite point of convergence or origin.
Some of the stains will exhibit dome shaped craters due to the sucking
process and others may show swiping due to defecation. These stains may
be observed on many surfaces at the scene expecially lamp shades,
blinds and ceilings as well as on the victim and clothing. Their
locations may be inconsistent with blood spatter associated with
injuries sustained by the victim." [19]
Although not true spatter, another pattern often confused with spatter
is the "fly speck" or "fly spot" pattern. Flies present within the
scene will feed on blood found there. This blood is both tracked about
and regurgitated by the flies. In the instance of the tracking pattern,
the marks are extremely small but a pattern may be evident on close
examination.
In the case of regurgitation, the specks are remarkably
symmetrical....Most often, the analyst finds these patterns in warm
areas where the flies rest, such as high in window corners or along
walls where the sun strikes. Such stains will usually test positive for
blood with a presumptive test. Obviously, care should be exercised in
evaluating any abnormal patterns which meet these criteria." [10]
However, no integrated approach by natural sciences and criminalists
had been used until actual case work (see cases below) and presentation
in courts, made it necessary to develop a method to safely distinguish
between blood spatter caused by force and blood spatter-like patterns
produced by flies.
This is expecially important since even artifacts caused by flies may
very well include the vicitim´s blood. Neither presumptive blood
tests like Hemastix (2190)/Heglostix (Bayer 028165A; hemoglobin
catalyzes oxidation of 3,3´, 5,5´tetramethylbenzidine
(color reagent) by diisopropylbenzole dihydroperoxide from green to
blue), Sangur (Merck), or Luminol, nor DNA typing will differentiate
between the two types of stains. This leaves recognition of stain
patterns and other physical information as the relevant criteria. The
following text illustrates stains produced by the activity of flies and
suggests methodology for evaluating stains in a decomposed body scene.
Furthermore, from the above quotes it appears that some documentation
of the crate was possible. In many countries, it is however unlikely
that a blood stain pattern expert will enter he actual scene and
therefore, documentation of crates has, to our knowledge and does
usually never take place.
2. Blood Spatter Types
Blood that is subjected to a low velocity impact (less than 1.5 m x
s-1); resulting blood spots often around 4-8 mm in diameter) is called
low velocity blood spatter. It is caused by free-falling blood under
the influence of gravity, including blood cast off from fist shoe, or
weapon.
Blood spatter as reported in the following three cases was usually
thought to be caused be either high velocity impact, or by a mixture of
medium to high velocity impact. Those types of spatter are defined as
blood subjected to a medium velocity impact (about 7.5-30 m x s-1),
e.g. blows with a hammer, or axe (medium velocity; spots typically
measuring about 4 mm in diameter), or blood sources that are subjected
to a high velocity impact (>7.5 m x s-1), e.g. a gunshot (blood
spots typically < 1 mm in diameter) [9].
3. Case I: Double homicide in Nebraska
3.1. General Scenario
The remains of two men were discovered at 14:25 hrs on 14. June 1997 in
in a third level apartment in a five-plex apartment building in urban
Lincoln, Nebraska, USA [23].
Both victims were fully clothed; both had a gunshot wound to the head
and gunshot wounds to the torso. One victim was found face down in the
kitchen area and the other victim was prone on the living room floor on
carpeting. Pools of a reddish substance were observed around the bodies
of the victims.
The bodies were in the active decay stage with black putrefaction only
just beginning; the skin was intact everywhere except where there were
gunshot wounds. At the wound sites, there was dried blood and body
fluids and in the areas around the bodies, flies, maggots and pupae as
well as some adult flies were present. The temperature registered 30
°C on the wall thermostat.
3.2. Forensic Entomology
On 15. June 1997, at 06:45 hrs, the police collected six adult flies,
three third instar fly larvae and several hundred first instar fly
larvae in ethanol from the scene. Adult flies had probably gained
access to the apartment by an open space beneath the front door. Both
adults and larvae were identified as Phormia regina (MEIGEN)
(Diptera:Calliphoridae) [20], the black blowfly and concluded from the
presence of small, first instar larvae and large, third instar larvae
that two distinctly separate periods of egg-laying by adult flies had
taken place.
3.3. Blood Stains
Initial observation of the scene gave the appearance of extensive low,
medium and high velocity blood spatters. Above the position of one of
the victims numerous stains of the low-high velocity type were found
(fig. 1). Similar areas were found on a kitchen hanging lamp, the
interior and exterior of the entry door, the bathroom, the two bedrooms
and the walls around the victims. The stains were tested positive for
blood with a quick test for hemoglobin (Hemastix/Heglostix)
The first assumption to be made was that there had been slinging of a
lot of blood around the kitchen and living room. This would suggest not
only gunshot wounds, but considerable movement of the victim and
suspect(s). It could suggest a motive of robbery, burglary, assault, or
a surprise attack. Examination of the kitchen and living room did
neither indicate struggling or fighting to any great amount. In the
bedrooms and bathroom there were flies, but no signs of bloodstain
patterns. There were no maggots in these rooms. The conclusion we made
was that not much activity had taken place in the bedrooms or the
bathroom of an assaultive nature and the bloodshed had taken place in
the kitchen and living room.
Recostructing the angle of impact of many of those stains, however, led
nowhere. There was no indication that the bodies had been moved and
there were no signs of a struggle in the bedrooms, or bathroom.
Smaller, round type spatters were mostly < 3 mm in length and >
1 mm in diameter. Furthermore, stains of a sperm-like shape
(irregular, uneven form with tail much longer than the body) as well as
a missing systematic directionality were observed. Since all stains
were composed of blood, how did they (a) get into all of the rooms and
(b) transferred to the walls?
3.4. Experiments and Measurements at the Scene of Crime
It is known that after feeding, flies regurgitate and defecate. Hence,
flies could have caused stains, containing blood of the victims, by
regurgitation, defecation and transference. In such cases, it is
expected that presumptive blood tests would indicate the presence of
blood. To prove that the unusual bloodstain patterns originated from
the body of the victims, whereas the mechanism of transfer was provided
by adult flies, the ratio Ltl/Lb (lenth of tail/length of body) was
calculted as 3,3 ± 2,4 [table 1]. Such a high value will not be
reached unter most case conditions, especially since not only the
calculated angles of impact but also the directionality of the stains
never point into one direction as would be expected from a violent
impact on a source of blood. Also, a mixture of round, symmetrical and
teardrop-like stains was found to be highly suspicious for fly activity
(fig. 3 b).
Additional tests under laboratory conditions on vertical paper surfaces
with adult Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae)
blow flies matured and maintained at room temperature (20 -- 25°C)
and supplied with a reddish-brown food mixture, let to the following
results:
• After one day in a breedings cage, of 304 stains,
112 (36.8 %) had a round shape whereas 192 (63.2%) had a tear- or
sperm-like shape.
• The directionality measured along the longer axis
of the tear- and sperm-like stains did show a random distribution of
stain orientations with an artificial preference for the top left
where a window (light source) was situated. In this experiment,
orientation was directed into the following directions: 42.8% upwards
left, 19.8% upwards right; 19.3% downwards left; 18.2% downwards right.
• The ratio Ltl/Lb was 1.5 ± 1.6 (n =
80) (i.e., tendency towards ratios >1).
However, single stains will not provide results that are statistically
sound. Although the ratio does not conclusively identify a stain as a
fly artifact, it provides a tool to eliminate suspect stains (see also
5.).
3.5. Conclusion
With information that stains appearing as human blood spatters were fly
artifacts, coupled with other scene evidence, we felt confident that
the possibility of an execution or revenge slaying could be put into
the mix of suspect behaviors at our crime scene.
4. Case II: Corpse of Lonely Woman
In Summer 2001, a dead female person was found in her bedroom in an
urban appartment in Cologne, Germany. The body had entered dried-out
state of decay with severe undernourishment during lifetime and an
underlying minimal greenish discoloration of the face and the abdominal
area after death. In the anal region of the corpse, few blow fly
maggots (oldest larval stage L3) were found. As soon as the windows
were opened, adult Lucilia sp. entered the room. Therefore and because
of numerous dots in the face of the dead person, the police asked if
blow flies had been present, or if those dots had to be attributed to a
source to be investigated on.
The windows were closed before the police entered which explained the
presence of only few flies, mostly pupae of phorids (Diptera:
Phoridae), was in accordance with the reconstruction of events. Apart
from piles of empty pizza delivery cardboard boxes and cigarette butts,
which did not provide food sources for blow flies, the appartment was
very clean and expensively furnished. The bathtub was half filled with
discolorated water that was most likely used to wash clothing.
Since the entrance door was regularly locked and no signs of a violent
fight were present, a reddish spatter field at a fan chain in the
kitchen became of interest (fig 3 c,d). The kitchen was located two
rooms away from the sleeping room and there was no visible evidence
that linked the kitchen to any violent event. Closer examination led to
the conclusion that the stains were fly artifacts. Since the eyes of
the corpse were still intacts and not used as a food resource by
maggots, it was concluded that only very few adult individuals of a
smaller fly species had been living in the appartment at some point
before, or at the time of death. Those few individuals used the fan
chain as a resting place and deposited reddish material with a typical
preference fort he lower border of the surface. The same effect is
present in fig. 3a under laboratory conditions, yet in a much larger
scale, where the flies also preferred the bottom border of the hanging
piece of paper.
Because of the nature of the stains, they were neither taken into
account for the further police investigation nor the reconstruction of
the events at the scene. The case was considered to be self neglect in
contrast to killing, or neglect by another person.
5. Case III: Slaying of mother and child
On 30. January 2001, the dead bodies of a mother and her child were
found in the living room of their house on the border of the city of
Cologne, Germany. They had been dead for around six hours. Another
child that had been sleeping upstairs was alive and not hurt. Blood
stain patterns were used to determine the course of events.
The crime scene reconstruction based on blood spatter became important
to check the statements of an accused man who owned a knife that was
used for the stabbing. For legal technicalities (rights of inheritance)
it also became important if the woman, or her child had been killed
first. Thridly, the defense lawyer wanted to proof that his client had
stabbed the child with brutal force to make clear that his client had
no mental control in the moment he performed the stabbing. Apart from
medico-legal considerations, it was thought that the velocity of the
blood spatter might help to address theses questions.
Amongst numerous other reddish stains in the house (in this case, due
to a local police procedure, all stains determined as originating from
the victims by DNA typing), few very small stains on a lamp were
observed. This lamp was located only ca. 1,80 m over ground and had
been hanging directly between the locations where the two bodies were
found. The police asked if these stains were caused by the impact of
violence, or by flies. As in most cases, the presence of flies was not
looked at by the first team which entered the house through a window.
After that, all flies may have flown out of the window. Therefore, a
combined blood spatter and forensic entomology expert statement was
asked for by the police and later again requested by the judge during
the trial.
The tiny, round stains on the lamp were distributed over the complete
surface (fig. 3). Genetic fingerprinting led to one conclusive DNA type
out of six stains (DNA of the child was found in one stain, no result
in the other stains). It was discussed that the stains might have
originated from the offender´s knife that got stuck in the
vertebra of the child (as documented by the forensic pathologist). When
the offender took the knife out of the bone with a jerk, few tiny
droplets of blood may have been distributed with a relatively high
initial velocity but got slowed down due to the resistance of the air.
On the other hand, since a possible patterning as in fly artifacts
could could not be ruled out with certainty (fig. 3d), no absolute
statement could be made about the nature of these stains. In the court,
we reported that because of the season of the year (winter) and the
state of the house (no rotting organic material present), it was less
likely that flies had produced the stains but that it was more likely
that the blood actually shed off the knife during the stabbing.
Droplets then reached the lamp at least at two seperate events whilste
the lamp was rotating around ist axis. Since the lamp was located ca.
in the height of an adult central European person´s head,
rotation was most likely induced by the people moving and maybe
fighting, inside of the room during the crime.
6. Practical hints
From our case work experience and from our experiments, the following
suggestions and techniques are offered for use in differentiating
between fly artifacts and human bloodstain patterns (fig. 4).
1. Document fly activity at a scene. Flies will be at a scene if access
to the scene is available to them. They will stay at the scene as long
as a food source is available to them and/or as long as they are
trapped. Therefore, check for dead flies, too. If evidence of flies is
present at the scene, assume that fly artifacts will be at the scene.
Follow standard protocols of description of insects at crimes scenes
[2,3,22] – where, when, how many?
2. Document the range of stains. Fly activity will often
concentrate near light sources, on light colored walls, windows and
mirrors. They will often be present in rooms away from the body.
Compare stains away from the body with stains near the body.
3. Compare stains with known fly artifact patterns.
4. Identify suspected human bloodstain patterns that are of the "spot"
or "tear" drop pattern that offer a potential for use in reconstruction
and eliminate the following:
a. Stains that have a tail/body (Ltl/Lb) ratio greater than one,
b. Stains with a tadpole/sperm type structure,
c. Stains with a sperm cell type structure that do not end in a small dot,
d. Any stains without a distinguishable tail and body,
e. Any stains with a wavy and irregular linear structure,
f. Any stains that do not participate in directionality consistent with
other stains that suggest a point of convergence at a point of origin.
Larger fly artifacts, within a group, will point in all directions.
Cast off human blood will produce stains, within a group, that
indicates a common general convergence point.
5. Note the absence of known human bloodstain pattern
characteristics. The absence of misting around a concentrated mass
would suggest the stains might not be from human cast off blood origin.
Within a group, human cast off patterns often leave secondary wave cast
off patterns and run off patterns.
6. Cover blood stains, especially on the floor, with paper sheets to
prevent them being destroyed by investigators walking on the stains.
7. One or two stains do not make a case. Stains that could be fly
artifacts should be eliminated and an evaluation based upon stains that
can be explained in terms of origin and relevance to the
reconstruction.
8. Use a high resolution camera with a macro lens and include a scale
in every single picture.
Forensic scientists, crime scene technicians and investigators may
encounter blood spatter at a scene which may be pure or a mixture of
fly artifacts and human bloodstains. It is important to be able to make
an informed identification, or at least advanced documentation of such
stains.
Acknowledgements
Dr. Brett Ratcliffe, University of Nebraska (Lincoln), performed the
species determination of the flies and kindly agreed that his findings
were used in this article (Case 1). Saskia Reibe, University of
Cologne, performed many of the measurements in laboratory conditions
(Case 1). Prof. Klaus Hausen and Mucki Döring, Universiy of
Cologne, kindly allowed us to us to use his flies and fly stables from
his neurophysiological laboratory for experimentation. The Cologne
Homicide Detective´s Bureau (KK 11; Cases 2 and 3: Detectives
Frank Kolvitz and Rolf Wingert) and the Cologne KK 53 (Crime Scene
Unit, head: Achim Wolff) were and are most helful in inviting me to
crimes scenes for case work as well as research purposes. The reviewers
provided us with excellent comments.
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Lesetipps
- Leichen-"Entsorgung" in einer Biotonne GERMAN TEXT
- Berechnung der Liegezeit mit Hilfe von Maden GERMAN TEXT
- Vorlesungsraum wird zum Tatort GERMAN TEXT