Defense tactics in cross-examining expert witnesses.

[Cindy Rennie]

I was wandering around the internet the other day and found several websites sponsored by various associations of defense attorneys. Some of these websites shared suggestions on the types of questions to ask forensics witnesses in the witness stand and methods to 'down-play' the impact of forensic evidence.

Among the sites were the National Association of Criminal Defense Lawyers. (www.nacdl.org). Click on "Champion Magazine" icon, enter "cross examination" into the search field. Most interesting are the two articles entitled "Preparing to Cross-Examine an Expert Witness". Part 1 deals with fingerprint testimony; Part 2 with laboratory testimony. Very interesting.

You can also search "forensics" and obtain other articles written by and for defense lawyers.

There is also a website for the National Legal Aid Defender Association.
(www.nlada.org). Click on 'Defender Resources' and then 'Forensics Library'.

If anybody has any more, please let me know.

[L.J.Steele]

If anybody has any more, please let me know.

There's a number of books and articles about cross-exam. In Massachusetts and in Connecticut, every courthouse has a law library, open to the public, which will include some journals and a variety of treatises with advice on topics like cross-exam. I don't know if Canadian courthouse also offer public law libraries. If not, try your local law school -- tho those tend to be more academic than practical in their materials.

Some libraries will offer a search engine for the Index to Legal Periodicals, and/or Lexis and Westlaw's law review database. Again, you will find many articles on cross-examining experts, and a few on fingerprint issues.

There are usually state and national organizations that offer continuing legal education (CLE) lectures on a variety of topics. Fingerprint challenges have been a hot topic in the wake of Mayfield, Cowans, and now Patterson. Ask your local prosecutor or defense counsel who provides these lectures in your area. Often you can get the written materials and audio recordings, which may give you an idea what information is circulating in your area. (A number of the course providers are looking for knowledgeable speakers on forensics, contact the program if you are interested.) Likely, the local prosecutor and public defenders' office have done internal CLEs about forensic topics -- these materials are usually only available to their members but ask nicely after a training conference and likely someone will be willing to give you the materials rather than tossing them out.

[L.J.Steele]

Just to add to the prior post.

I work in appeals. I see a half-dozen to a dozen criminal trial transcripts per year, mostly in Connecticut and Massachusetts. In the vast majority of these cases, the direct and cross-exams are superficial. The prosecutor has the expert go through his or her credentials, introduces the fingerprint enlargments as exhibits, give the expert's conclusion, and explain very briefly how it was reached. The defense cross-exam is usually quite brief.

This is a very limited sample set -- not many cases, all cases where the defendant was convicted, and (due to the delay in obtaining transcripts) mostly pre-Mayfield, Cowans, and Patterson. But for the most part, unless the defense attorney hired an expert who disagrees with the prosecutor's expert's conclusions, you are unlikely to see a detailed cross-exam. The defense theory will be to get you, and your damaging testimony, off the stand as quickly as possible and to move onto some other area. You might get questions about innocent access, but generally won't get detailed challenges.

Two other possible defense theories are (1) fabrication -- the print matches but did not come from the crime scene; and (2) an honest, but mistaken, mis-ID. Both of these are more likely if the print is the only evidence placing the defendant at the scene -- no confession, no eyewitness, no DNA or other trace evidence. If the defense theory is, for example, self-defense, consent (in a sexual assault case) or that the defedant is guilty of a lesser offense than what is charged, then there's no reason to belabor the forensics testimony.

This may change. And there are some attorneys doing more thorough jobs. You could, I think, fairly expect questions about....

(1) fabrication and forgery -- is the print consistent with the location where the print was allegedly found, is it consistent with how the object would have been handled during the crime, are there holes in the chain of custody.
(1a) if a digital image was used, questions about its authenticity and any errors that could have been introduced by the process of taking and manipulating the digital image.
(2) the famous errors -- questions asking you to explain Mayfield and Cowans and why the same error could not have happened in your case.
(3) blind vs. non-blind verification -- questions about Patterson's criticism of verification and what the verifying examiner knew when he or she reviewed the ID.
(4) questions about the "zero" error rate -- likely from someone who read Cole's article and/or the N.E. Innocence Project brief in Patterson. (Kasey W has all of the briefs on the clpex site.)
(5) questions about confirmation bias, tunnel vision, and stress -- likely from someone who read the NACDL brief in Patterson.
(6) questions about basis of your testimony -- you may get asked if there are peer-reviewed, published materials that support your testimony, particularly if you are using a technique or theory that the attorney has not encountered before.
(7) Things that could have been done, and were not, to find the prints of other culprits (usually used in combination with innocent access and a claim that some other person is the true culprit).

And a thorough attorney will have read your c.v. in detail and have checked it. If you've written any published articles, don't be surprised if the attorney has read them. You may get asked about materials from training classes, and what books and magazines you consider authoritative.

Don't be surprised when the attorney gets technical terms wrong. This is usually not some clever trick, but likely someone who just doesn't know the technical terms for your field or understand why the distinctions are important. (It may be worth going over terms with the prosecutor ahead of your testimony to make sure he or she uses them correctly.) Attorneys are used to using words precisely, but in their legal context, which may not be the same as your professional context. As a note, talk with the prosecutor about technical terms to make sure that the court reporter spells them correctly in the transcript.

[L.J.Steele]

One other thought -- do not be surprised by a limited cross in depth cross-exam in a capital case. I know this sounds odd -- you'd expect the defense attorney to be fighting over every scrap of evidence with the client's life on the line.

Problem here is that a jury in a death penalty case must be "death qualified", i.e. the jurors have to state in the voir dire that they are willing to vote for execution if the evidence supports it. Research and attorney experiences suggests that a death-qualified jury is less inclined to acquit on the evidence, even when there are significant issues of guilt. Moreover, that same jury will review the defense evidence in the sentencing phase. Some attorneys are concerned that if they put up a fight on the evidence, and lose, they will have blown their crediblity in the sentencing phase and the client is more likely to be executed.

I'm an appeals attorney -- I've never had to make those tactical choices. I disagree to some extent with my colleages, but I accept they've got more experience in these matters. If we accept the Stacey report on Mayfield, then high-profile cases with press/political/admin/internal pressure to find and convict the bad guy will tend to produce confirmation-bias type errors. It is precisely in death cases where, I fear, there is a greater risk of error. And it is here, where attorneys may be less likely to aggressively challenge questionable forensics for tactical reasons if they expect the client to be convicted regardless and are trying to save his life.