In this segment, I’ll talk a little about some specific challenges you may have to your testimony. Most of the advice here is not specific to private practice, but some is.
There are a couple of formal challenges to testimony that can become important in trial. These have never happened to me in my usual ME duties, but occasionally occur in my private cases. Counsel may attempt to get you kicked out altogether or they may attempt to put boundaries on what you can testify against. You should take these challenges seriously, because failing to be certified as an expert at trial is something that folk always ask about. If you have failed to be certified as an expert, then you will have to explain why over and over again in the following years.
If you have stayed within your lane in your opinion and have a good scientific and literature basis for it, then you will be fine. I’ve mentioned previously that I am fairly careful to provide a citation/literature base for my conclusions in my private reports. This is one of the reasons. It can nip most of these kinds of challenges in the bud. It’s hard to say there’s no basis for my opinion when I include 10 citations for it.
The two kinds of challenges that have come up to me are voir dire and Daubert.
Voir dire
Voir dire is a legal term for questioning where the opposing counsel will try to get you excluded from testifying or put constraints on your testimony. This can happen as a pretrial hearing (not in front of the jury) but it’s mostly happened to me while I’m on the stand when I’m submitted as an expert (in front of the jury). This is not really a challenge to the scientific basis of your opinion, but more whether or not you are qualified to act as an expert. The circumstances where I get voir dire’d more often are:
- When the opposing counsel claims that Forensic Pathology as a specialty does not provide sufficient training to allow subspecialty testimony. For instance, I testified in a child abuse case a little while ago. Counsel challenged my ability to testify because I was not certified in Pediatric Pathology. I basically had to show that training in pediatric issues was part of forensic pathology training, that I had experience in evaluating child abuse cases, and such. This can also come up in head trauma cases where I’ve been challenged because I’m not certified in Neuropathology. I’ve also been challenged because I was not “certified” in patterned injury evaluation (which should be amusing to those of you who know me). These challenges are easy to deal with. All you have to do is emphasize that such training is part and parcel of forensic pathology training, and give a few examples. Often they will ask “How many such and such cases have you done?” I never kept count, so I can’t answer that, but it has never really hurt me (but I wish I had kept count). I simply point out that these kinds of cases are not all that uncommon in practice.
- When the opposing counsel claims that the issue in question is not a Forensic Pathology question at all. This usually comes up in cases where I am testifying in a case in which the victim survived. The challenge is that Forensic Pathologists know about dead people, but are not qualified to opine about injuries in living people. I point out that this is an “inappropriate distinction” and note that had the victim not survived, the injuries would not magically change. Similarly, counsel may claim that since I “only” deal with dead people, I don’t know how to evaluate vital issues such as healing. I point out that when there is an interval between injury and death, evaluating injuries is very important, both to trace back the kind and severity of the original injury but also in estimating time of injury. Finally, if you do this enough, you will be able to say that you have testified in multiple cases involving living subjects.
- There’s an error in your CV or similar problem with your claims of education, training, etc. Sometimes folk make mistakes on their CVs. Usually the errors are minor and unimportant. But don’t try to fake things.
- You might have some blot on your record or have been denied certification as an expert in an previous trial. Be sure to have an explanation for that.
If there’s a major challenge that will take some time, the judge may have a separate hearing. Most often, this happens to me at the beginning of my testimony. My side will present my qualifications in front of the jury and ask that I be certified as an expert. Then the opposing counsel will be given the opportunity to do voir dire. I’ve seen this kind of thing in trial transcripts when the pathologist decides that he or she wants to opine on ballistics, engineering aspects of traffic collisions, and stuff like that. We may know a lot about terminal wound ballistics, but you might be challenged when you decide to talk about firearms and such.
The key here is that this kind of challenge is pretty much the same for every trial that comes up. Put together a response and keep it in your pocket. You’ll use it over and over again.
Daubert
Prior to 1993, the standard for admissibility of expert testimony was based on the 1923 Frye standard. It stated that a conclusion could be presented if scientific principles were “generally accepted” in the field. In 1993 the Supreme Court ruled in Daubert v Merrell Dow Pharmaceuticals that the judge should determine whether or not testimony was “scientific” based on the court’s vision of the “scientific method.” There were two subsequent rulings, General Electric v Joiner (1997) and Kumho Tire v Carmicheal (1999), that fine tuned the idea. In the dissent in Daubert, justices Rhenquist and Scalia noted that the ruling turned judges into “amateur scientists” and sorta violated it’s own essence since judges with poly sci degrees may not be the best folk to evaluate how “scientific” an opinion is. There seemed to be a lot of confusion in the 1990s and early 2000s about this when I was testifying. In my personal experience, it has functionally devolved back into Frye in practice with a few more bells and whistles.
There’s a lot written about Daubert, and this is not a handbook on the subject, so I won’t drone on any more about it in the general sense. It really rarely comes up in “normal” ME practice because what we do is pretty cut and dried, and the principles we use have been hammered out.
I had a lot of experience in Daubert hearings because I did a fair amount of image processing and computer vision work just when digital photography was coming into use in the 1990s. A lot of folk challenged digital imaging findings back in the day, saying that only film photography was “reliable.” Something like this came up in the trial of Kyle Rittenhouse, the kid who shot three people during riots in Kenosha Wisconsin in 2020 and was acquitted on the basis of self-defense. The prosecution attempted to introduce “enhanced” images into the case in which the enhancements were essentially AI-based rather than image-feature based. The argument against its use was that AI can confabulate and the reliability of the method was not proven. I don’t know if it was a formal Daubert challenge, but that would have been appropriate. In the trial of Derek Chauvin in the death of George Floyd, the prosecution introduced what appears to me to be an unvalidated, unproven, and novel model of deformation of the hypopharynx to support the claim of asphyxia. This should, in my personal opinion, have had a Daubert challenge, but it did not.
Daubert challenges can be intimidating, but they can also be a lot of fun. I remember one case in the early 2000s where I underwent a hearing that lasted something like eight hours. I had been hired by the prosecution in that case. The defense attacked my methods, my training, and my integrity. She said I didn’t know what I was doing, and on and on and on. About four hours in, the judge called a lunch break. The defense counsel came up to me and told me she was having trouble with her laptop. I spent a bit of the lunch break helping her troubleshoot her machine. After we got it up and working, I got back on the stand and she spent another three hours calling me incompetent.
After she was done with me, the *judge* started harassing me and asked me more questions for about another 30 minutes or so. After I was done, I sat down, exhausted. I was convinced I’d screwed it up. Cohttps://wordpress.forensicpath.us/index.php/2024/12/07/private-consulta…ges-to-testimony/unsel told me not to worry, I’d done fine. He said that everybody knew the defendant in this case was a monster (it was a rape-murder case and it wasn’t the defendant’s first rodeo). He knew it, the judge knew it, and the defense knew it. The reason that the Daubert hearing went on so long was that everybody wanted every possible question to come up so that when the judge ruled in my favor there would be no basis for appeal. If the judge rules in my favor, the judges on appeal will tend to defer to the trial judge on every question he or she rules on, but may rule in favor of the defendant if there were challenges that were not made that might have been important. That was why the judge was asking me questions — he wanted to cover the areas that the defense missed.
Because Daubert is about the “scientific basis” of your opinion, you need to be able to back up every step of your inferential process with some sort of literature. If you’d done some sort of little study for the case, then you need to show that its valid. Also, you need to learn a little about the “scientific method” and “scientific inference” and be able to show that your inferential process is “scientific”.
I recently talked to one of my lawyer friends about this challenge a few weeks ago. He told me that Daubert challenges were not nearly as common as they used to be and were really only used when something very novel comes out of left field.
One of the problems, I think, is that nobody knows what they are doing. Lawyers have a hard time asking the right questions because Daubert challenges really can get into the weeds of methodology. Most lawyers don’t have enough of a scientific background to know what to ask. As a consultant on the challenging side, you can help with that, but you can’t ask the questions for them. Back when I got a lot of these, it seemed like the lawyers had been to a seminar or two on Daubert and knew the buzzwords, but didn’t know where to go if you had any answer at all. They were basically hoping that you were as clueless as they were and would get flustered. It quickly devolved into personal attacks.
Daubert challenges can also mix unrelated standards. Many years ago, I had a Daubert challenge to some image processing I did in a case. This was back when film photography was still dominant, so in order to do the processing I had to digitize a print using a scanner. An expert hired for the Daubert challenge said that my image processing was invalid because the scanning was done at 600 dpi, while the “industry standard” for scanning was 3600 dpi. The “industry” that he was talking about was for the scanning and long term storage of kinds of documents. It not the same field I was working in, but since it was a “standard” I had to deal with it in my testimony. It was clear that neither the lawyers nor the judge had a clue what either one of us were talking about.
Both of these formal challenges might happen to you. You should brush up on both of them.
Other informal challenges:
Here are a couple of more informal challenges I’ve had.
Topic exclusion:
I’ve had a couple of challenges to specific points in my testimony based on technical legal points that I did not understand. The judge said I could testify, but not express specific opinions. I don’t know, but this seems to be for specific issues for specific trials. The one I remember had to do with a manner determination. Those of you who know me know that I don’t believe that manner should be admitted at trial at all. The judge ruled that I could give the opinion of whether manner determination was correct or incorrect, but could not discuss my opinion that manner doesn’t belong at trial. This was a problem, since one of the principles of manner determination is that there is sometimes no absolutely “correct” answer and manner is determined by convention. It was difficult for me to argue that a manner was “wrong” when that concept of correctness may not apply at all — but I couldn’t say that. Eventually I just gave the arguments against a particular manner and left it at that. I’ve never had much input into these things, but your client might ask you in preparation for a hearing.
Bias challenges:
Bias challenges seem to have become much more popular in the past decade. They tend to be attacks rather than actual attermpts to keep you from testifying. As a method of trying to impeach your testimony, however, it can be a hassle. Basically, it is a combined personal and methodologic attack suggesting that your conclusion is not based on the facts, but instead on some personal bias you have. There are a lot of kinds of bias, but the one that seems currently popular is that of “contextual bias.” The accusation is that you have allowed contextual data, e.g. history that was provided to you, the race of one of the principals, aggregate statistics, etc to influence your conclusion.
This can be a *little* difficult to deal with because history and circumstances are part and parcel of medical diagnosis. The claim made by proponents of this kind of challenge is that physicians are no different than fingerprint experts, and should make their diagnoses based on no, or limited, information. This is absurd, of course, but there you go. One such proponent, Itiel Dror, stated that it is simply not the role of the physician to integrate contextual data into diagnoses except in specific circumstances. The claim is that contextual data is not “medically relevant,” though nobody has ever really defined how medically relevant is determined — in fact Dror indicated that he did not believe that the medical community was competent to determine what was medically relevant.
One feature of this debate that I believe is important, and very telling about the ideologic basis of this, is that proponents of the bias attack have no data indicating that error is increased by involving contextual data. In fact, they explicitly do not care. In “real” science, you would establish a base error rate, do the intervention, and see how it changed the error rate. They don’t want to do that. I personally believe they know that the interventions they propose will increase rather than decrease error, and they don’t want to face that.
This is, fundamentally, a political and ideological attack based on a specific view of the role of the pathologist. The best you can do is provide an argument of why the contextual information you used *is* medically relevant, and be explicit about how your diagnosis would change if the contextual information was incorrect.
Another useful defense for my Medical Examiner work is to invoke peer review. Most ME offices have some sort of peer review program as part of their quality control system. It can help on the stand to say that your conclusions were reviewed. It’s harder to say that in private cases, since you usually don’t have peer review, but you can say that your cases as a ME are constantly reviewed and contextual or personal bias have not been an issue. Since it hasn’t been an issue in the other few thousand cases you’ve done, so it likely isn’t an issue in this case. I was recently in a child death case as a defense witness where the prosecution expert — a pediatrician board certified in “Child Abuse Pediatrics” went on at some length about how that she submitted all of her determinations for peer review. I’m not sure how much it impressed the jury.
One option, if you see this coming, is to try to get your client to pay for another expert, and have some sort of peer review. I don’t know that this works all that well or not. I know of a couple of private consultation businesses that use it as a business model, and it seems to work for them. I was recently asked by a major news outlet and the family of a decedent to review a high profile death. I told them that I would not do it individually, but would get a panel to review the case. The result had a lot of credibility. Since the results were not what folk wanted to hear, it never was published in the press, but the conclusions were rock solid (and my thanks to you who worked on that panel — you know who you are, and I’m sorry the results were never made public). In general, counsel has not been eager to pay for more experts.
A similar challenge is that of personal prejudice. I have been called sexist, racist, classist, etc. on the stand. As always, it’s hard to defend yourself against these attacks, since they are based on assumptions rather than fact. The example I like to give is the claim that I didn’t believe that rape happens because of a literature review I posted on my website. I went into this in the last post when discussing social media, so I won’t belabor it. The best I can do is address the specifics of the attack and let the rest just wash over me. The key here is just to not take anything personally, not get angry or defensive, and, when in doubt, say less than more. It has been fairly useful for me to say “That is absurd,” and just move on, though you really have to read the room when it comes to a jury to decide how voluble to be. It’s usually better to say less than more; if more is needed, then counsel can bring it up on redirect or recross and provide a path for rehabilitation.
This personal prejudice thing is why I tend to steer clear of social media other than this blog. I don’t want to have a casual joke I made come back to be blown up out of nothing and presented to the jury as some sort of foundational prejudice. The same thing is true of mailinglists and private email. I’ve gone back to section 6 of this series and added a bit about that.