How do they decide who are the FBI's 10 most wanted criminals?
According to the FBI web site, the Criminal Investigative Division (CID) at FBI headquarters calls upon all 56 field offices to submit candidates for the FBI's "Ten Most Wanted Fugitives" list. The nominees received are reviewed by Special Agents in the CID and the Office of Public and Congressional Affairs. The selection of the "proposed" candidate(s) is forwarded to the Assistant Director of the CID for his/her approval and then to the FBI's Deputy Director for final approval.
There are two criteria for criminals on the list. First, the individual must have a lengthy record of committing serious crimes and/or be considered a particularly dangerous menace to society due to current criminal charges. Second, it must be believed that the nationwide publicity afforded by the program can be of assistance.
—The Fact Monster