Our adversarial justice system requires that the government’s attorney seek justice, not simply a finding of guilt. If we adhered to that principle, there would be no problems with forensic science. But we don’t. We too often see government attorneys who have forgotten what their jobs are supposed to be. It’s at those times that forensic science is abused, when lab analysts can be pressured.The government lab employee then must decide between his family’s future and security and presenting an unbiased opinion. He is stuck with an ethical dilemma. On top of that, there is almost no accountability if he decides to cheat. The easy way out leads to revelations of malfeasance decades later, when he is retired and beyond any real accountability.On the other side of the courtroom, we see defense counsel fully educated to the fact that forensic disciplines are seriously flawed, yet nevertheless looking for experts willing to say anything for a fee. A system in search of the truth would adhere to Daubert and its progeny [the U.S. Supreme Court decision that established ground rules for expert testimony], and both sides would scrupulously screen their own experts. This is common sense, but we ignore it.
The “crucible of cross-examination” is a convenient canard deployed so courts will continue to admit unreliable evidence, allowing the (scientifically illiterate) lawyers [to] argue to (scientifically illiterate) jurors about the weight that ought to be given to unscientific expert testimony.
Court-appointed experts seem like a good solution to the problem of over-partisan experts. However, they are much more problematic than it would appear. In regard to admissibility (reliability) hearings on proposed expert testimony out of the hearing of the jury, the court could bring in its own expert, but it could not, especially in criminal cases, deprive a party of the right to call the party’s own expert to dispute the positions of the court-appointed expert — or even to corroborate and supplement them. So you’d end up with three experts instead of two. And if courts are not great at evaluating conflicting expert testimony, there is no reason to believe they will be better at picking an expert in a controversial area to begin with. Someone also has to pay the court-appointed expert. So although a court could do this, it is rarely done.The issues regarding admissibility hearings apply even more acutely to testimony in front of a jury. The defendant has a right to put on a qualified expert of his choosing, and there would be objections that the court-appointed expert’s evaluation would be accepted by the jury without any real evaluation, based on the expert having been blessed as “neutral” by the court. And now we are back to the question of the court’s ability to select the “right” expert in a contentions area.The term “hot-tubbing” was coined in Australia for the process of making the experts hired by the two sides of a case enter into dialogue to expose their points of agreement and disagreement. There are a number of approaches to the details of the process, but it is a more practical possibility than court-appointed experts. Still, there are problems. It is not clear that a criminal defendant can be forced into submitting their expert to a “hot-tubbing” experience. More substantively, there is some reason to believe that, just as the views of the more aggressively smooth and confident expert may be accepted by the jury independent of their tenability or weight upon rational reflection, that same witness may be able to sway the hot-tubbing dynamic in favor of his or her employer. So while I believe that properly structured “hot-tubbing” can be of use, it is not a panacea. Nor do I know of any other panaceas.
I don’t agree that good scientists cannot be trained to become effective experts, but I do think that there are some charismatic, persuasive experts who are completely unqualified to give opinions, but are still allowed to testify by the courts. Judges either lack the capacity to assess their qualifications, or the charlatans are simply never put to a challenge by overworked public defenders.I have reviewed cases where police officers with no credentials, who took a two-week course on blood stain analysis, were declared experts on blood evidence interpretation. I have reviewed cases where “human factors” or “reconstruction” experts were giving opinions on the decedent’s injuries and proceeded to dive fully into the realm of forensic pathology, a medical specialty that requires a doctor’s degree coupled with years of subspecialty training. Here’s the foundational problem: In order to be declared an “expert” in court today, you only have to convince the judge that you know more than the average person. That’s it. There is no minimum education requirement, training protocol or credentialing process for expert witnesses.Furthermore, it’s not unusual for multiple well-qualified experts with excellent credentials to arrive at conflicting opinions on a case, based on their differing experience and training. If one expert is working for the defense and the other for the prosecution, jurors usually assume that their differences in opinion are due to financial incentives rather than legitimate differences in scientific analysis or professional experience. If forensic experts were hired and paid for by the court, rather than by either the prosecutor or the public defender, then the courts could ensure the experts were credible and articulate, and there would be no financial incentive for the expert to please one side or the other. After a trial, the jury should be asked or required to evaluate all the experts based on the clarity of their scientific testimony, with their anonymous feedback going to the experts so that they can learn and improve. We need to professionalize the task of expert testimony.
Courts should fund experts for defendants, and in the event that the defense expert and the prosecution expert are in disagreement, the court should hire its own expert. I have served as a court-appointed expert on three occasions, and it is gratifying not to have the pressure from either side. I just get to tell the judge what the science is and what the evidence shows. I try to do that in all my cases, but am sometimes limited to “just answering the question.”The “hot-tubbing” of experts used in Australia and in some European countries [in which experts from both sides and a court-appointed expert confer and come to a conclusion before trial] has been tried, and initial reports that I have heard are very positive. If the experts can get together and agree on the issues that they agree on, then only the areas of contention need to be litigated.
There is a lot packed in here. I am not sure that the “qualities and characteristics of a good scientist are contradictory” to a jury’s expectations and needs. Witness credibility hinges on too many factors to be linked to one feature or characteristic.I have not thought enough about whether an “independent” expert system is any better than what we have; those “independent“ experts may also have their own biases or institutional pressures. And there are many ways to reduce bias and work toward the “search for the truth“ that you set as the goal — consider, for example, the work of Itiel Dror and others on reducing bias in expert analysis and reporting.
For many reasons, I agree that our adversarial system is a very flawed way to assess expert testimony. I don’t agree, however, that the qualities of a good scientist would necessarily be incompatible with persuasiveness. A good scientist, who is also a good teacher, should be able to explain things in ways that jurors would find understandable and, therefore, if appropriate, persuasive.Nevertheless, there are many reasons that our system is bad for assessing the testimony. First, that experts for opposing sides testify separately — hours or days or weeks apart — makes it difficult to assess that evidence. One might argue that the time delay happens for much of the evidence, e.g., both sides might call different eyewitnesses to the same event. That’s true, but for things that are novel or at the limits of jurors’ understanding, one longer, deeper presentation, where both sides are presented and cross-examined in sequence, might be better. (Also, jurors should be allowed to ask questions — submitted to [the] judge and attorneys first to check for admissibility.)But second, I believe that a better approach is not to have two sides. Having opposing experts can be unfair, in that one side might have resources that the other side does not (typically prosecutors have more access to forensic scientists than public defenders do). It also can be misleading. For example, one side might represent what an overwhelming majority of experts would say, and the other might represent an extreme minority view, but they look to the jury as if they are of equal scientific value.
It is difficult not to think that resolving scientific controversies could be improved by adopting a process less formal than American legal proceedings.In particular, I think greater clarity could be achieved by, for example: (1) airing the scientific controversy in writing as much as possible, rather than orally, so that the contestants can muster evidence, make careful argumentation and so on; (2) allowing the contestants to pose questions and answers to one another, to try to identify points of agreement and disagreement, and so on.Legal proceedings are “performative” — they are theater. There are some good reasons for this in a trial. But admissibility hearings don’t have juries, and it is a little silly to require scientists to go to a particular place and time and speak their science into a microphone to be transcribed into writing by a court reporter — all constrained by formatting one’s science in the form of answers to questions posed by one, two or three (in the case of the judge) lawyers, who probably do not understand the science very well. There is a better way: the written report.
The language that forensics experts use to explain their conclusions shouldn’t be the focus here. Forensic experts have long used exaggerated and unscientific terminology. The FBI audit of testimonial overstatement in hair evidence was shocking.But as Greg Mitchell and I have found in a series of studies, it is much more important for jurors to hear real information about the reliability of the evidence. Jurors need to hear about error rates and about the proficiency of individual experts. They want to know how good the evidence is and how good the particular expert is. We should tell them. Judges can do that without excluding evidence. In fact, Greg and I have found that jurors can quite rationally incorporate this information into their decisions.
In addition to the issues that I described in my previous answers, as per the misuse and abuse of science within the adversarial system, there are a few steps we can do within the existing system. For example, in the United States, lawyers “rehearse” with the experts, preparing and guiding/instructing them how to answer. This is not allowed in the United Kingdom. Lawyers cannot tell the expert what they are going to ask them in court, let alone hear their answer and give “feedback.” This is one simple example that would help minimize the adversarial misuse of experts.
I would urge some caution on the idea of court-appointed experts. While independent, court-appointed experts can sometimes be helpful to minimize the bias inherent in the adversarial process, it is dangerous to think that a court-appointed expert or experts will necessarily reflect true neutrality or truth in science. Many scientific questions legitimately have competing scientific perspectives. Simply having the court appoint one, or even a group, of experts does not necessarily ensure objectivity or truth. If the court happens to appoint the wrong experts, the legitimate dissenting scientific views will be unnecessarily and unfairly muted, or even silenced.
My book argues that the National Academy of Sciences got it right when it recommended that crime laboratories exist and operate independently from law enforcement organizations. In the early 2000s, a major scandal broke out over the pervasive problems with the Houston Police Department Crime Laboratory. As a result, city officials handed over control of the laboratory to an independent organization, creating the Houston Forensic Science Center. By making the lab an independent government agency, the city elevated the status of the lab, making it a co-equal partner with the other stakeholders in the criminal justice system — the district attorney’s office, the public defender’s office, local law enforcement and the judicial system. Since its establishment five years ago, the laboratory has gone from a failed organization to a model laboratory with unparalleled quality controls and highly efficient procedures.