Because the right side of the road was full of cars waiting for a light to change - the wrong side of the road was not. Given a choice between running up the back of a line of cars at traffic lights at 50mph, or crossing to the empty side of the road, I know what I'd choose.
This is pretty much where I live. I'm less than a five minute drive from where he stopped. He'd just come off the freeway because it had ended - they'd kept him on it as long as they could and the police were trying to get him to a rural highway that's about a mile away down a fairly major road. But there was too much traffic here.
I think he probably panicked and that's why he didn't manage to stop earlier - if he'd done at the start of the drive what he did at the end, it might have worked - but unless it's some sort of elaborate fake out by the police, they believe his story, and they were there. Two of them were preparing to ram him off the road (and I'll tell you, a typical Victoria police car against a Ford Explorer would not be pretty for the cops)