Scientific Evidence

At the same time that DNA evidence was being closely scrutinized by the courts and Kumho was prompting renewed judicial interest in nonscientific expert testimony, several notorious cases of scientific malfeasance received extensive treatment in the news media (Giannelli, 1997). One case is illustrative. Fred Zain, the former head serologist of the West Virginia State Police crime laboratory, falsified conventional serological test results in as many as 134 cases from 1979 to 1989. Defendants, since exonerated, were sentenced to long prison terms based upon his testimony. A judicial inquiry concluded that "as a matter of law, any testimonial or documentary evidence offered by Zain at any time in any criminal prosecution should be deemed invalid, unreliable, and inadmissible" (In re Investigation of the W. Va. State Police Crime Lab., Serology Div. , 438 S.E.2d 501, 520 (W. Va. 1993)). In 1989, Zain accepted a serologist position with the County Medical Examiner's laboratory in San Antonio, where he performed DNA profiling and testified in death penalty cases. Another instance of misconduct involved New York State Troopers who tampered with fingerprint evidence.

Despite the publicity that the cases of intentional misconduct generated, there is good reason to believe that in at least some crime laboratories simple incompetence is a more prevalent problem—often traceable to inadequate funding (Giannelli, 1988). There is a widespread feeling that courts should rigorously police the reliability of proffered expert testimony to give the laboratories an even greater incentive to select trustworthy scientific tests and to use meticulous care in conducting the tests.