One study suggests that, among American men between the ages of fifteen and thirty-four, the number who were treated in emergency rooms as a result of injuries inflicted by police and security guards was almost as great as the number who, as pedestrians, were injured by motor vehicles.

In eighteenth-century New York, a person held as a slave could not gather in a group of more than three; could not ride a horse; could not hold a funeral at night; could not be out an hour after sunset without a lantern; and could not sell “Indian corn, peaches, or any other fruit” in any street or market in the city. Stop and frisk, stop and whip, shoot to kill.

Police patrolled Black neighborhoods and arrested Black people disproportionately; prosecutors indicted Black people disproportionately; juries found Black people guilty disproportionately; judges gave Black people disproportionately long sentences; and, then, after all this, social scientists, observing the number of Black people in jail, decided that, as a matter of biology, Black people were disproportionately inclined to criminality.

In 1965, President Lyndon Johnson declared a “war on crime,” and asked Congress to pass the Law Enforcement Assistance Act, under which the federal government would supply local police with military-grade weapons, weapons that were being used in the war in Vietnam. During riots in Watts that summer, law enforcement killed thirty-one people and arrested more than four thousand; fighting the protesters, the head of the L.A.P.D. said, was “very much like fighting the Viet Cong.”

More Americans went to prison between 1965 and 1982 than between 1865 and 1964, Hinton reports. Under Ronald Reagan, still more social services were closed, or starved of funding until they died: mental hospitals, health centers, jobs programs, early-childhood education. By 2016, eighteen states were spending more on prisons than on colleges and universities. Activists who today call for defunding the police argue that, for decades, Americans have been defunding not only social services but, in many states, public education itself. The more frayed the social fabric, the more police have been deployed to trim the dangling threads.

Wilson’s work informed programs like Detroit’s stress (Stop the Robberies, Enjoy Safe Streets), begun in 1971, in which Detroit police patrolled the city undercover, in disguises that included everything from a taxi-driver to a “radical college professor,” and killed so many young Black men that an organization of Black police officers demanded that the unit be disbanded. The campaign to end stress arguably marked the very beginnings of police abolitionism. stress defended its methods. “We just don’t walk up and shoot somebody,” one commander said. “We ask him to stop. If he doesn’t, we shoot.”