When a crime is committed, and traces are gathered at the scene or otherwise obtained, comparing these traces to a database is now a standard means of identifying a suspect or suspected item. Traditionally, forensic scientists used fingerprints and shoeprints in this way. When Smith is identified through a database search, and his name is passed on to the police, they may or may not find other evidence. If Smith is in fact the donor, and it is a recent and important case, people may expect to find some other evidence supporting Smith as the donor. The forensic scientist can observe a match but not whether it was an adventitious or a true match. The database search controversy is an example of a general situation in which suspects or suspected items become the focus of interest as a result of some operation on a database that records certain features of a number of persons or items.