As indicated in chapter one, scientific evidence is far more prevalent today than it was one hundred, fifty, twenty-five, or even ten years ago. At least three factors have fueled the virtual explosion of science into evidence. One is the astonishing and accelerating pace of scientific discovery and technology. A century ago, x-rays and blood groups were unknown or just being discovered. Now, CAT scans and DNA are household acronyms.
Science has much more to say today.
Second, the federal and uniform rules of evidence, adopted in most jurisdictions some twenty years ago, removed various barriers to the admission of expert testimony. In the most extreme cases, vicious murders have been said to have resulted from exposure to television or ingestion of carbohydrates, and birth defects of unknown etiology have been attributed to medicines or spermicides. It has seemed as if somewhere, somehow, some expert could be found to blame almost anything on something else. Thus, lawyers used to enlisting partisan experts in legal causes now draw not merely on medical doctors and coroners, but also on economists, epidemiologists, geneticists, psychologists, statisticians, toxicologists, and many other specialists to dispense opinions favorable to the parties sponsoring them. Judges, practitioners, law professors, and scientists of all stripes were quick to offer their answers.