"This is the right decision for me, and something that I have given a lot of thought to," Brent explained in a statement released by the Cowboys. "I am at a point where my main focus is all about getting the priorities in my life in order. Those priorities are more important than football. Doing the right things in life are more important than football. I love the game very much. I love my teammates, but this is the right thing for me to do."
Brent is awaiting trial on an intoxication manslaughter charge in connection with the December 8 car accident that killed practice-squad linebacker Jerry Brown Jr.
"I promised Jerry's mother that we would support Josh in every way we could," Cowboys owner Jerry Jones said, via The Associated Press. "That's been our only thought since the accident is to support him and support our team in their support of him."
The NFL was expected to make a decision on Brent's playing status before the start of training camp next week. The Cowboys had been hesitant to release Brent, reportedly hoping to retain his rights in the event of a long suspension. A source told NFL.com's Albert Breer, however, that the idea of returning to football someday "isn't even a part of (Brent's) thinking right now."
Cowboys coach Jason Garrett told ESPNDallas.com on Thursday that "it's premature" to discuss the possibility of Brent returning to the Cowboys should he come out of retirement. NFL spokesman Greg Aiello told NFL.com's Ian Rapoport that "any request for reinstatement by (a) retired player must be reviewed and approved by the league."
Brent played three seasons for the Cowboys, recording 44 tackles and 1.5 sacks in 39 career games.
Follow Chris Wesseling on Twitter @ChrisWesseling.