Cop(s) blocking

[[TC]►Ras◄]

You summed it up fairly well. Basically,

Since MRT's don't have a reverse gear, don't deliberately drive around it and block it's front, however you don't have to do anything if the driver of the MRT put themselves into that situation (as in, you were already at a standstill and the MRT drove with the front against your car - Their own fault, then.)

If someone happens to stop their car with front or rear against a wall or anything that can't get knocked over, then that is their own fault and you don't have to move away as it is their own fault. Although if it happens, it is likely a bad place for a traffic stop and you should ask them to pull over properly on the side of the road anyway.

And yes, if the suspect attempts to run, don't go and block their way deliberately before they failed to stop, so they get a chance to initiate a chase.

Now, while none of this is written in the rulebook, it is pretty much common sense for people who wants to play the game the way it was intended to.