Silent Witness - Volume 7, Number 2, 2002
Preparing for Defense Experts
by Lisa Kreeger, Director, APRI’s DNA Forensics Program
What should you do when you learn that the defense announces their intent to use an expert witness to assist with the DNA evidence in your case? Initially – do not panic! Secondly, prepare your response, bearing in mind that the DNA evidence is merely one piece of evidence in your entire case.
The prosecutor focuses, organizes and controls the evidence presentation to ensure that the fact finders will reach the correct result. Treat the defense DNA expert accordingly, i.e., as a witness whose testimony is controlled by preparatory research, anticipatory pretrial motion work, motions-in-limine regarding trial testimony and focused cross-examination. This newsletter reviews specific actions prosecutors can take to preclude or limit a DNA expert from controlling the content of the testimony.
Assess Your Evidence Strength
Learn as early as you can whether there could be a credible defense attack of your DNA evidence and specifically what it could be. When your DNA analysts provide a report to you, ask if there are any foreseeable criticisms, attacks, concerns, or problems. Do your analysts believe any issue was created in the seizure, storage, submissions or handling of the evidence? Do the analysts believe there is any procedure, policy, or practice of the lab that could be criticized for failing to meet appropriate scientific standards? Did anything different or unusual happen with the evidence or the analysis in this case? Confirm that the analysts are confident in finding a match between crime scene evidence and the defendant, their analysis of a mixture and the major or minor contributors, and about the statistical conclusions that can be drawn from the analysis. Review with the analysts all of the other evidence in the case to make sure that the DNA evidence is consistent with all of the facts. Examine whether your analyst will testify to the absence of DNA evidence in certain aspects of your case. (Experts can rely upon a wide variety of sources to form their opinions, including knowledge of the facts of your case.) Learn from your expert witness whether a defense expert’s testimony would be a good faith challenge and not misleading to the fact finder. When there are no identifiable issues relating to the DNA (or lack thereof), focus on preparing your case as a whole.
Limit the Role of the Defense Expert
Evaluate the facts and anticipate the defense in the case. The better in command you are of all the facts and all the plausible defenses, the better positioned you are to successfully exclude or limit the defendant’s expert. While the existence of DNA evidence may eliminate an identity defense, you should develop all identity evidence, including the traditional evidence of motive, opportunity and post-crime guilty behavior. By bolstering the identity evidence, your argument that identity is not the defense in the case is stronger. If identity is NOT the defense, then what legitimate purpose (or testimony) will a DNA expert offer? If identity is not the defense, then the expert’s testimony is irrelevant. Challenge the defense’s ability to call an expert whose testimony will be a general criticism of science or statistics.
If the defense lists or announces a potential defense witness, ask on the record what purpose the expert will serve. Challenge the defense lawyer to articulate the need for and the testimony of the expert in your case because you will hold the expert to those limits. Get into your record, either by proffer in court or by pleading, a demand for a specific description of the expert’s testimony.1 Additionally, inquire and force an answer from the defense regarding whether the defendant wants to test the DNA evidence. For a number of post-conviction reasons2 a defendant’s desire to retest is important, but not testing the evidence should limit or possibly exclude the defense expert’s testimony at trial.3 You should record the following by way of submitted letters and/or discovery pleadings: (1) that there are remaining samples from this case are in your lab; (2) that you are willing to allow for retesting; and (3) that an opportunity will be afforded the defense expert to retest the evidence. When the defense expert does not retest, move before trial for permission to cross-examine the expert on his awareness of the remaining sample and his opportunity to retest.
Research the Expert’s Credentials
Get as much discovery material from the defense lawyer as you can, including the expert’s fee amount and the parameters of the expert’s compensation. Learn who the defense expert is in the forensic science community.4 Is this person a forensic DNA examiner, a non-forensic scientist, an academic, or a population geneticist? Has the expert worked in a lab? If so, when, where, doing what and for how long? Examine the witness’s resumé, biography, or curriculum vitae for what is and is not there.
Compare information provided by the expert with additional information found in the cyber or real world. Conduct an identity search on any of the Internet’s major search engines. Search NEXIS, LEXIS and WESTLAW for references to the expert. Opinions reciting a court’s refusal to find someone to be an expert are persuasive support for a motion to exclude a witness entirely.5
Then, call APRI or other resources that may have transcripts or unpublished opinions that refer to the defense expert. Find out if the transcripts reflect the expert’s qualifications to testify in your case, given your facts and your DNA evidence. Call or contact resources to confirm the credentials and qualifications of the expert. Ask your analyst and others in your lab to use their professional resources, including neighboring labs or the FBI, to gather information about the expert. Compare what the expert’s testimony has been to what the defense purports to be the expert’s role in your case. If the expert’s credentials are inconsistent with the purported defense challenge to your evidence, move to exclude the expert.
Preparing for Cross-Examination
Compare and contrast sharply the specific scientific, forensic, and non-forensic, work experience of your analyst and the defense expert. Which expert works on forensic science cases, solely, in a lab that is accredited or working towards accreditation? Which expert is in a lab every working day of the year? Who works daily with other qualified scientists available to review the expert’s work? Who has examined the evidence in the case? When did the defense expert learn about the case? If the defense expert has not tested the evidence, move to limit the defense questioning or exclude it entirely. When the expert has no personal knowledge regarding the analysis of your DNA evidence, request that the defense be precluded from asking any questions regarding the lab or the match. Finally, who can contextually analyze the DNA evidence with all of the other evidence in the case? While DNA evidence is not complicated, do not allow the defense expert to talk about unrelated, general scientific or statistical issues.
Conclusion
DNA evidence is just one form of identification. It is not the determinant of guilt. DNA is, however, an easily validated and trustworthy science. Similarly, statistics is not new or fuzzy math. Consequently, a defense expert cannot attack the fields of science and statistics credibly. To be relevant, experts should challenge facts in a case. Put the defense expert’s criticism in proper context. Understanding the purpose and consequent import of the defense expert’s testimony, given all of the evidence, enables you to control it. The background of a defense expert is most meaningful in a context of comparison to your case. Move to exclude or to limit the expert’s testimony as completely as possible. If the expert cannot testify to case-specific, fact-specific issues relating to the evidence, the analysis, or the conclusions of your witness, then the expert’s testimony really is irrelevant, a waste of judicial money and time.
The APRI DNA Forensics Program has several pertinent Motions in Limine and Demands for Discovery.
See State v. Norton, 949 SW2d 670 (Mo. 1997); State v. Gentry, 888 P2d 1105 (Wa. 1995); and State v. Jobe, 486 NW2d 407 (Minn. 1992).
See Maryland v Gross, 134 Md.App. 528, 580 (Md. 1999).
Click here for resources referred to in this article. Resources prepared for presentation by ADA Mitch Morrisey, Denver, CO
See Maryland v. Gross, 134 Md. App. 528 (Md. 1999).
|
