Chris Brown -- I'm NOT Copping a Deal in My Assault Case

Chris Brown just REJECTED a plea deal in his Washington D.C. assault case.

Brown was in court facing an assault charge in connection with his run-in with a guy outside his D.C. hotel in October.

The prosecutor revealed in court they had offered Brown a deal -- reducing the charge to simple assault (he currently faces misdemeanor assault which carries a more severe penalty), but Brown's lawyer, Mark Geragos -- who was also in court --- rejected it ... and we think we know why.

Law enforcement sources tell us ... they had combed the area looking for surveillance video capturing the run-in. For a long, long time they said they had nothing. Now they seem to be singing a different tune, but haven't turned the video over to Geragos.

Geragos -- who believes his client did nothing wrong -- is eager to see the video before cutting any kind of deal.