Justin Bieber -- Toronto Limo Assault Dropped

Justin Bieber is walking away clean from his assault case in Toronto ... the charges have been dropped.

Bieber's case was scheduled to be heard in court Monday -- he was charged with criminal assault of a limo driver back in December -- but today the prosecutors announced the charges had been withdrawn because it was unclear who actually made contact with the driver. There were 5 other people in the limo besides Justin.

Bieber's attorneys have been busy in the last few months ... settling up his cases in Miami, L.A. ... and now Toronto.