Help with wiring problem

I got hit in the back of the car last week and since then the rear windscreen wiper won't stop wiping (ever!). I just want a simple solution so I was wondering:

1. Is it okay to cut the wire to the wiper?
2. Which wire do I cut (and how)?
3. Will I electricute myself?
4. Is anything else on the circuit (like the front wiper)?

Its a 1990 standard Toyota Corolla.

Thankyou!

just figure out which fuse it is and pull the fuse. make sure that you're not cutting off anythign else though...the fuse box will be on the driverside kick panel (right by the door) or under the hood on the right side as you're standing in front of the car