Charges have been filed over a spitting incident on a Winnipeg bus caught on camera.

Winnipeg police have charged a bus passenger with assault for spitting on the driver in front of Polo Park Wednesday. Police say 29-year-old Matthieu Joseph Fortier is charged with assault and is detained in custody.

Court records show he has prior convictions for robbery and assault.

Const. Rob Carver said following a disagreement over the fare, the passenger in the video became aggressive and eventually spits on the driver. The driver can then be seen running after the passenger off the bus, at times swinging his fists and eventually with the help of others, he detains the man until police arrive.

Carver said the driver is not facing any charges and acted properly given the situation.

"There's often no way to detain someone who's been very aggressive, who has assaulted you, without potentially to use some force," he said.

Pat Montgomery was waiting at the stop at Polo Park where it happened. She feels the driver did the right thing.

“I felt very sorry for the bus driver and he reacted well,” said Montgomery

The city may see it differently.

The Amalgamated Transit Union said city policy dictates drivers stay in their seats and not follow aggressive passengers off the bus.

"The thought behind it is safety. I mean, you know once you get off that bus what's going to happen. Is it going to escalate? Could that person have a weapon?" said union president John Callahan

Bus rider Kayla Graham said the driver went too far and should have followed that protocol.

"The guy was off the bus. He could have just drove away," said Graham

But Callahan said that's easier said than done. "Cause you're confined in that compartment, you're a sitting duck. So a lot of operators, when they feel the threat, they just want to get out of there,” he said.

Callahan said of the 60 assaults on Winnipeg drivers last year, most involved a dispute over fares. He said the union wants a new system in place where drivers aren’t responsible for collecting fares.

Callahan said the driver was shaken up by the incident and is not working right now, because he's not feeling up to it. It's unclear at this point if the city will take any disciplinary action against the driver.