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Several forensic sciences, especially of the pattern-matching kind, are increasingly seen to lack the scientific foundation needed to justify continuing admission as trial evidence. Indeed, several have been abolished in the recent past. A likely next candidate for elimination is bitemark identification. A number of DNA exonerations have occurred in recent years for individuals convicted based on erroneous bitemark identifications. Intense scientific and legal scrutiny has resulted. An important National Academies review found little scientific support for the field. The Texas Forensic Science Commission recently recommended a moratorium on the admission of bitemark expert testimony. The California Supreme Court has a case before it that could start a national dismantling of forensic odontology. This article describes the (legal) basis for the rise of bitemark identification and the (scientific) basis for its impending fall. The article explains the general logic of forensic identification, the claims of bitemark identification, and reviews relevant empirical research on bitemark identification-highlighting both the lack of research and the lack of support provided by what research does exist. The rise and possible fall of bitemark identification evidence has broader implications-highlighting the weak scientific culture of forensic science and the law's difficulty in evaluating and responding to unreliable and unscientific evidence.

For the past two decades, the American judiciary has confronted the admissibility of hypnotic evidence in criminal prosecutions. These courts have uniformly rejected the admissibility of out-of-court statements made while an individual is in hypnosis. In contrast, the courts divided sharply over the admissibility of hypnotically refreshed testimony. Some courts adopted a per se rule of exclusion; these courts, however, also carved out exceptions for testimony based on prehypnotic memory and testimony of the accused. Courts admitting hypnotically refreshed testimony adopted three different positions: (a) a "credibility" approach, which left the reliability issue to the jury; (b) a "discretionary admission" approach, which left the reliability issue to the trial judge; and (c) a "procedural safeguards" approach. In addition, constitutional concerns played an influential role in some of these cases. This diversity in the case law often resulted from a judicial failure to understand the scientific research on hypnosis. Courts have also considered the use of hypnosis as a basis for expert testimony about an accused's mental state. Unless the advantages of hypnotically refreshed testimony are significant, why add more problems?