Brown, 25, had failed to agree to the no-jail plea accord by a noon deadline, attorneys at a District of Columbia Superior Court hearing said. The deal would have sentenced him to time already served.
The "Turn Up the Music" singer was charged with misdemeanor assault after Parker Adams, 20, claimed Brown and his bodyguard Chris Hollosy punched him and broke his nose when he tried to jump into a photo outside a Washington hotel in October 2013.
Hollosy was convicted and is appealing.
The Washington hearing was part of series of scrapes Brown has had with the law. He was released this month from a Los Angeles jail where he was serving a one-year sentence for violating probation from his 2009 assault of pop singer Rihanna.
Brown had been locked up since March 14 after he was kicked out of court-ordered rehabilitation in California for violating rules. He must also undergo therapy and random drug testing and complete community service.