Many criminal and civil trials revolve around scientific evidence, but rarely does such evidence elicit the response received by DNA tests. Since November 1987, when a Florida criminal conviction based on DNA typing received national attention, interest in using DNA tests in crime laboratories throughout the country has soared as have civil liberties concerns. Standards for forensic uses of DNA typing; funding of crime laboratories, forensic personnel training, and forensic research; the advisability of establishing computer databanks of DNA test results; standardization of DNA analysis for improved data collection; and privacy considerations of collecting, using, and storing DNA data or samples are all being considered for action by the U.S. Congress. Although the standards and additional quality control needed to be used in forensic DNA testing may be debated, no scientific doubt remains that technologies already available can accurately detect genetic differences between humans. Recombinant DNA technologies are new, powerful tools to clear the innocent and convict the guilty. 289 references, 25 figures, 19 tables, and appendix