Question : If I’m in a safe passing zone marked 80km and have 2 cars in front of me, after passing the first vehicle, do I have to then go back to the right lane before overtaking the second vehicle or can I stay in the left lane and continue passing if there are no oncoming vehicles?

If I remain in the left lane and am approaching to pass the second vehicle, do I have the right of way or would they? Is the onus on the vehicle in front of me to use their mirrors before crossing the center line and make a left turn across the roadway while I’m getting ready to pass them?

Although using common sense is always recommended, the BC Motor Vehicle Act does have a few things to say about this: 

Duty when overtaking

157 (1) Except as provided in section 158, the driver of a vehicle overtaking another vehicle

(a) must cause the vehicle to pass to the left of the other vehicle at a safe distance, and

(b) must not cause or permit the vehicle to return to the right side of the highway until safely clear of the overtaken vehicle.

(2) Except when overtaking and passing on the right is permitted, a driver of an overtaken vehicle,

(a) on hearing an audible signal given by the driver of the overtaking vehicle, must cause the vehicle to give way to the right in favour of the overtaking vehicle, and

(b) must not increase the speed of the vehicle until completely passed by the overtaking vehicle.

Passing on left

159 A driver of a vehicle must not drive to the left side of the roadway in overtaking and passing another vehicle unless the driver can do so in safety.

Clear view on passing

160 A driver of a vehicle must not drive to or on the left side of the roadway, other than on a one way highway, unless the driver has a clear view of the roadway for a safe distance, having regard for all the circumstances.

So, yes you can do it as long as you remain within the law (above).