Let's say the police patrol presence in your area was tripled. Would you feel safer? If you were a criminal, would be feel more afraid? A now-infamous year-long study showed that most likely you wouldn't even notice.
In 1972, the police in Kansas City, Missouri, tried a year-long experiment to see how random police patrols helped reduce crime in neighborhoods. The department played around with the 15 "beats" they already had in the city. In five of the beats, they eliminated random patrols, and only reacted to crimes as they were reported. In five beats, they kept the police patrols running just as they always had. In the remaining five beats, they tripled the amount of random patrols.
The results were so discouraging that the disappointment is evident even in the dry language of the report. Bullet point by bullet point, it spins out a tale of indifference, if not total ignorance. It starts out with, "the experimental conditions had no significant effect on... crimes traditionally considered to be deterrable through preventive patrol." These included burglaries, car break-ins, vandalism, or robberies. The report continues by saying, "there were few significant differences... in terms of citizen attitudes towards police services," and "citizen fear of crime, overall, was not affected by experimental conditions," and "attitudes of businessmen towards crime and police services were not affected." The crime rate didn't change. The traffic accident and injury rate didn't change. Response time to crimes didn't change, nor did satisfaction with response time. Nobody even noticed the difference.
Granted, this was the '70s, and police procedures may have changed since then. The study noted that more than half of the time spent "patrolling" was actually just spent in the car waiting for calls. The rest of the time was evenly split between police patrolling and "non-police activities."
It's odd that no one, either criminal or civilian, even noticed that the police presence disappear from a section of town, or triple in another section of town. It makes me wonder what would happen if someone tried to instate a police state, and no one noticed. Could all it take for evil to be defeated is for good people to do nothing — and not even notice?