The changes that departments are considering include revising core training standards and tactics, reassessing when and how to make arrests, and re-evaluating how officers approach and interact with members of the public during street and traffic stops.

At the forefront are de-escalation tactics, the variety of methods officers use to defuse potentially violent encounters, such as talking and behaving calmly and reasonably with sometimes unreasonable people…

For police departments, the question is whether today’s standard model of aggressive policing — based in part on the broken windows theory of making arrests and issuing citations for even the most minor offenses — is compatible with a more progressive goal of simultaneously catching criminals and building greater trust within neighborhoods.

“I was trained to fight the war on crime, and we were measured by the number of arrests we made and our speed in answering 911 calls,” said Kathleen O’Toole, the Seattle police chief, who is overseeing the department’s changes as part of a consent decree with the Justice Department.