While not available under normal circumstances, the Police Maverick is obtainable in Grand Theft Auto IV. First pick up a sniper rifle, and go way to the Happiness Island. Climb the base of the tower until you get to the highest point (where you can obtain the T-shirt). Use a regular weapon to kill the guards nearby (to get the wanted level) as well as the few that come running from below. Since the island has no access roads, no reinforcements can be sent (other than the helicopter.) Next, wait for the helicopter to arrive. The next part is somewhat more difficult. Use the sniper rifle to kill one of the policemen in the rear (the officers shooting at you.) The helicopter will now turn around to give the other cop a clear shot. Shoot this one in the shoulder, causing him to drop the assau