" The first Kansas City experiment said that preventive patrol was useless, that having more police cars driving around made no difference. The second Kansas City experiment amended that position. Actually, extra patrol cars did make a difference—so long as officers took the initiative and stopped anyone they thought suspicious, got out of their cars as much as possible, and went out of their way to look for weapons. Patrol worked if the officers were busy. The statistics from the final report on the experiment were eye-opening. "
― Malcolm Gladwell , Talking to Strangers: What We Should Know About the People We Don’t Know