Tools of the Trade: How the Courtroom Calls Upon Science
This entry is part of a series on the role of science in the federal judiciary. The complete series can be found HERE.
As discussed in the last post, Sound Science in an Adversarial System, there are court rules governing admissibility of scientific evidence. Yet in cases where scientific and technical understanding is key, there are also special roles and resources that are designed to help the judge or jury.
Expert Witnesses. Expert witnesses come equipped with specialized knowledge (e.g., science!) and are expected to speak to this knowledge. Expert witnesses offer their specialized knowledge and their interpretation of this knowledge, which is typically considered evidence in proceedings. They may or may not be familiar with facts of the case at hand, but they are almost always aligned with one of the litigants. As such, there is often a “battle of the experts,” with cross-examination and other court procedures.
Technical Advisors. Although this role is similar to that of expert witnesses, technical advisors are experts who are not affiliated with one of the litigants. A technical advisor’s role is not to advocate for one but rather to help the judge understand scientific jargon and theories relevant to a case at hand. Technical advisors may be court-appointed experts. When court-appointed, their communications may or may not be conducted ex parte (e.g., without the disputing parties present). The jury will not be informed of these communications.
Science Days. For some scientists a “Science Day” in the courtroom will almost appear like a scientific symposium, with multiple experts presenting technical information to the court before a trial. Unlike the usual courtroom day, a Science Day is not adversarial; the purpose is strictly educational, and cross-examination is not allowed. Science days are not common, but they can be a useful component of cases that revolve around complex and recent science. The exact format depends on what the parties agree to, so it may look different from case to case.
Amicus Curiae Briefs. Beyond presenting in person, scientists can also help write amicus curiae briefs. These documents are supplements to a case of broad public interest and submitted by someone other than a party in the case; the term literally translates as “friend of the court” (Amicus Curiae). The goal of an amicus brief varies, but for scientists, it typically would be to provide scientific information that is useful to the court in making a particular decision. Amicus briefs are growing in popularity. Although they are most frequently submitted to the Supreme Court, amicus briefs may also be filed in the federal district, appellate, and state courts. Anyone can help write an amicus brief, but there are specific rules on who can file what and when in different courts. In general, amicus briefs are an important way to help inform the court about scientific perspectives.
Reference Manual on Scientific Evidence. This publication is the fundamental guidebook for courtroom science. The manual is produced by the Federal Judicial Center and National Academies of Science, Engineering, and Medicine and the whole process is overseen by a committee of judges and scientists. Each chapter focuses on a specific field of science (e.g., DNA evidence, toxicology, neuroscience) and is written by a team of scientific experts in that field. The manual was first published in 1994, detailing subtleties of scientific disciplines over 1,000 peer-reviewed pages. The fourth edition, which includes chapters on topics such as Artificial Intelligence and How Science Works, is in press in 2024 and will be distributed to every federal judge after printing.
Judges and courtrooms can rely on varying combinations of these tools to understand science. Some may rely more on written resources and others value in person explanations from expert witnesses and technical advisors. Approaches may also change with different topics and case complexity. Going forward, increasingly complex scientific studies will require that scientific studies can be even more clearly and unambiguously communicated by experts inside and outside of the courtrooms.
