U.S. v. Trenkler

Two police officers were killed in 1991 when a bomb exploded at the home of Thomas L. Shay (Shay Sr.). After an investigation, Thomas A. Shay (Shay Jr.) and Appellant were charged; after Appellant filed a severance motion, each was tried separately and convicted. At Appellant’s trial, evidence that Appellant had been involved in another bombing in 1986 was admitted, and the prosecution’s expert testified that, “he had no doubt whatsoever that the same person built both bombs.” Also at Appellant’s trial, the prosecution offered evidence from an Alcohol, Tobacco, and Firearms (“ATF”) computer database; an Intelligence Research Specialist from ATF testified that, “in an effort to identify the builder of the [bomb at issue here], he performed a series of computer queries, focusing on characteristics of the [bomb].” The results of the test showed that the bomb that exploded at Shay Sr.’s home had several characteristics in common with the earlier bomb that Appellant was involved in making; by eliminating bombs that did not share certain characteristics, the “series of inquiries narrowed the filed of reported incidents in the database from 40,867 to seven.” Appellant was convicted and appeals the admission of the evidence here.