Max Keenan, aka Matthew Brennan, is the biological father of Russ and Temperance Brennan. A known criminal involved with gangs in the 70's, he and his wife switcthed identities to lead an honest life with their children. Max's first appearance on Bones showed him impersonating a priest to contact Temperance while he was involved in an ongoing homicide case that Dr Temperance Brennan and Special Agent Seeley Booth are investigating.Later in the second season, Booth arrests Max on murder charges and he is trialled in Season 3's episode, The Verdict in the Story . The jury finds him innocent on all counts and is released, and is finally given the opportunity to reconnect with his children.