Good one: brakes make it possible for bank robbers to travel faster than 80mph in a car, therefore the police must have a way to remotely disable brakes to catch escaping bank robbers. Oh you can trust the police the keep the brake-disabler safe from terrorists, don't worry.
So, if you want to try to use this metaphor, the situation is actually a little bit different. Try this:
"Seat belts make it safe to go faster than 20 MPH, and tolerable to go faster than 80 MPH. Unfortunately, sometimes bank robbers use them while going faster than 80 MPH, so we have to ban seat belts entirely to prevent them from robbing banks."