You are Judge Dredd. Your job is to track down unsolved crimes in Mega City and solve them. To do this you have your Lawmaster bike and your Lawgiver gun.
In Mega City solving crimes means shooting anyone who looks like a threat, a perp, a seed, and that's just about everyone.
It's a nice idea though. You start on a screen that represents Mega City. Around the city crimes are being committed, these are represented by white tiles saying 'arson' murder' etc. Your task is to navigate to each crime and hit the fire button. This takes you into that location where you blow everyone away in a platform like shoot 'em up. Then it's exit the location, go to the next, and repeat.