If you are trying to reduce precinct crime rates, go into a pharmacy. When you get inside, frisk everybody there. The following are the predicted amounts of people holding contraband.
High crime rate: Approximately everybody. Medium crime rate: Approximately 50% of the people. Low crime rate: Approximately two to five people.
Start at the back of the pharmacy. Work your way to the front of the pharmacy by arresting people with contraband. If the person is clean, walk them to the front of the pharmacy and release them there. Hide behind the back shelves when you arrest him or her so that no one else will see you. Do this so that nobody with contraband runs out of the place.