These laws, known as the Tiahrt amendments after their co-author, former Republican Rep. Todd Tiahrt of Kansas, should be repealed in full. Given the influence of the NRA in this Congress, however, repeal will probably have to wait for the arrival of less easily cowed legislators. In the meantime, Congress should confront the gun lobby on the issue that most directly hurts public safety: the inadmissibility of gun-tracing data in court. Police can't stop criminals if prosecutors can't bring them to justice.