The primary cause of police alienation

The primary cause of police alienation from the populace is the patrol car. Patrol cars like all automobiles insulate us from human person to person contact. A car is like a suit of armor: This is one of the major causes of road rage: people feel protected inside their "rolling armor."

If the police want to improve relations with the public they need to get out of their cars and "walk the beat" for at least half an hour everyday and get to know the people they are supposed to serve. This is especially true in urban and low income neighborhoods where many residents do not own cars. The exercise will do the officers some good as well.

This is how it was before the advent of the automobile and how it is in  many Japanese communities where police are generally well liked by the public and highly regarded.