But the law must seek decisions that fall within the boundaries of scientifically sound knowledge. Even this more modest objective is sometimes difficult to achieve in practice. The most obvious reason why is that most judges lack the scientific training that might facilitate the evaluation of scientific claims or the evaluation of expert witnesses who make such claims. Judges typically are generalists, dealing with cases that can vary widely in subject matter. Furthermore, science itself may be highly uncertain and controversial with respect to many of the matters that come before the courts.
Scientists often express considerable uncertainty about the dangers of a particular substance.
And their views may differ about many related questions that courts may have to answer. Many difficult legal cases fall within this area of scientific uncertainty. Finally, a court proceeding, such as a trial, is not simply a search for dispassionate truth. The law must be fair. In our country, it must always seek to protect basic human liberties.