|Portrayed by||John Finn|
|First Appearance||Look Again|
John Stillman is a lieutenant with the Philadelphia Police Department and commander of the cold case squad. A Vietnam combat veteran with some war-era stress as seen in "Honor" he has shown himself to be stern but caring boss. His daughter was once assaulted, but survived and gave him a grandson. Due to his commitment to the job, his marriage was very strained and finally ended in divorce. His older brother is a Catholic priest. In the fifth season (beginning in September 2007), he took the month's unpaid leave meant for Scotty Valens, in order to keep him on the force. Stillman, having reflected on his place in the police force during his suspension, later decided to retire, though later was inspired to return to duty when Lilly convinced him to help in a case ("Family 8108").