DECLARATION OF BRENT E. TURVEY
I, Brent E. Turvey, declare as follows:
1.
I am a forensic scientist. I am a senior partner in Forensic Solutions, a company
which provides forensic consultation and training, specializing in the areas of forensic science,
crime reconstruction, criminal profiling, and related subject areas. I make this declaration of my
own personal knowledge and, if called upon to do so, could and would testify competently to the
facts stated below.
2.
I have a Bachelor of Science Degree in Psychology and a Bachelor of Science
Degree in History from Portland State University. I further have a Master of Science Degree in
Forensic Science from the University of New Haven.
3.
I have performed casework as a forensic scientist and/or criminal profiler for law
enforcement as well as criminal defendants and civil clients, and have qualified as an expert in
over a dozen cases in the areas of Forensic Science, Crime Reconstruction, Crime Scene
Analysis, Case Linkage (Motive and Signature Analysis), Criminal Profiling, Staged Crime
Scenes, False Allegations, and Victimology.
4.
I am Secretary of the Academy of Behavioral Profiling, a Board Member,
Forensic Section of the Academy of Behavioral Profiling, and an Editor of the Journal of
Behavioral Profiling.
5.
I am currently an Adjunct Lecturer on Forensic Investigation and Criminal
Profiling in the Graduate Criminology Department of Bond University in Gold Coast, Australia,
and an Adjunct Professor in the Department of Criminal Justice and Sociology at Oklahoma City
University, teaching subjects on Criminal Profiling, Criminal Investigation, and Forensic
Science.
6.
I have published numerous peer-reviewed works including textbooks, textbook
chapters, and articles in reference manuals and professional journals. This includes the textbook
“Criminal Profiling: An Introduction to Behavioral Evidence Analysis”, of which I am the
author. This also includes the textbook “Crime Reconstruction” co-authored with criminalist W.
Jerry Chisum, and “Rape Investigation Handbook”, co-authored with Det. John O. Savino of the
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NYPD, Manhattan Special Victims Squad.
7.
I have performed forensic casework and research involving the interpretation of
the results of Luminol tests performed at crime scenes and on related items of evidence. I have
also published peer-reviewed literature on the subject of interpreting Luminol tests.
8.
I have been asked by attorneys Shari Greenberger and Sara Zalkin, counsel for
Jason Cai, to examine the forensic evidence in People v. Cai, with respect to both a possible
reconstruction of events and a motivational analysis of offense-related behavior. These findings
were detailed in my report dated January 4, 2006.
9.
In addition to those findings, I have been asked to further comment on the
Luminol tests performed in this case.
10.
Luminol is a presumptive screening test for human blood. A positive Luminol test
indicates the need for further testing to prove that human blood is present. Luminol tests are not,
and must not be used as, conclusive tests for human blood. Luminol cannot distinguish between
human blood and animal blood.
11.
Luminol is catalyzed by the presence of metal ions such as copper, iron, and
cyanide. Consequently, there are many things common to most environments that may result in a
false positive Luminol result. Luminol fluoresces in the presence of rust, copper or an alloy of
copper, certain bleaches and cleaners, and a variety of plant and vegetable matter. Luminol will
also detect the small amounts of blood present in urine.
12.
Luminol is best used as an investigative tool, to suggest the need for conclusive
testing, or to lead investigators to other evidence.
13.
Interpreting or representing positive Luminol results as a certain, conclusive
indicator of human blood an abuse of presumptive findings, and strongly indicates a training
need. A positive Luminol reaction may not be used to suggest that blood must have been in that
location, in the absence of other confirmatory forensic testing.
14.
Positive Luminol reactions to the hardwood floor, walls, dresser, door frame,
outside step, shower stall, and a dish towel, as suggested on p.4 of the People’s Response to
defendant’s Motion to Exclude Luminol Results dated March 8, 2006, do not lead to the
reasonable inference that a large amount of Ms. Deng’s blood, or anyone’s blood, was present in
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any of these areas. They lead to the suggestion that further, conclusive forensic testing is
warranted. Failing to achieve confirmatory results, it is not reasonable to go backwards and reinterpret presumptive findings in the light most favorable to a particular theory. There are too
many potential environmental contributors to eliminate before any one conclusive interpretation
can be reasonably inferred. For example, Luminol may simply be reacting with cleaning agents
used in the home, which would necessarily be on the towel and other surfaces that were tested.
15.
This examiner is unaware of any injuries to Ying Deng that would have resulted
in blood flow or bloodstain patterns. Consequently, this examiner sees no relevance of any such
blood evidence to the events that took place on the night of her death.
I declare under penalty of perjury under the laws of the State of California and the United
States of America that the foregoing is true and correct.
Executed this _____ day of March, 2006 in Sitka, Alaska.
___________________________
Brent E. Turvey
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