Last summer Chicago, like cities across the US, erupted in protest over the country’s long history of racism, particularly as represented by the most visible manifestation of the state’s monopoly on violence, the police.

Marchers flowed through the downtown streets at one June protest, chanting the names of George Floyd and Breonna Taylor, both killed by police officers performing their duties. Passing officers stationed at intersections, the crowd hurled a challenge. “Who do you protect?” they chanted. “Who do you serve?”

In some ways, Tangled Up in Blue asks the same questions. There is no way to understand the US without considering race, and no way to consider race without confronting the ugly reality that the country’s police officers, armed and funded by taxpayers, disproportionately kill black people. Georgetown University law professor Rosa Brooks shows policing from the inside, recounting the period she spent patrolling the streets of Washington as a volunteer police officer, a position I was surprised to learn existed.

At a time when activists are interrogating the fundamental value of policing, Brooks describes the mechanics of the job. She writes about bureaucracy, mental health crises, arresting people stealing food, the reality of violent crime, the systemic racism that officers don’t see and the casual contempt with which they sometimes display it. The book questions the way policing is done, while illustrating how hard it is to do the job.

A critic of the US criminal justice system, Brooks was shocked by her own impulse in middle age to join a Washington police department programme that trains residents to become part-time officers, complete with gun, badge and full arrest powers. She was curious, bored and wanted a challenge that was “nothing at all like a faculty meeting”.

Her decision appalled her mother, the writer and activist Barbara Ehrenreich. Author of the immersion journalism classic, Nickled and Dimed, Ehrenreich was a veteran of marches from the 1960s and 70s. She told her daughter when she applied, “The police are the enemy.”

American policing is “a breathtakingly violent enterprise”, Brooks writes, noting that the year she applied to Washington’s programme, US police killed more people in the first 24 days of 2015 than police in England and Wales killed in the previous 24 years. “Adjusting for population size, American cops kill people sixty-four times as often as police in the UK.”

Brooks is compelling on the everyday details of the work. She realises after donning her uniform that “cop swagger” comes from the weight of 30 pounds of gear: gun and holster, bulletproof vest, radio, baton and more. She lists more than 100 items that were used as weapons in 2018, including an iPad, spray deodorant and a pumpkin gourd.

Racism and sexism are here, like the officer who refers to the residents of his largely black district as “animals” or the training officer who gives recruits a series of ugly nicknames. (She mentally dubs him “Lawsuit”.) So, too, is “the blue wall of silence” when a union rep suggests she stay quiet about an officer’s harangue.

Brooks is careful to underline that crime remains a painful, frightening burden to the people who live where it is prevalent. She sympathises, too, with the stress that can turn cops cynical — “Sometimes, it seems like everyone you meet is crying or yelling”. Yet she also indicts police training and culture for overemphasising the job’s danger, making officers too ready to shoot.

When activists cry to “defund the police”, they want blue payroll funding diverted toward social services. For example, they don’t want cities to deploy police, who carry guns, to treat someone having a mental health crisis. That’s what happened in January in Killeen, Texas, to Patrick Warren Sr. The officer dispatched to the scene shot and killed him.

Eventually Brooks’ experience led to a joint project between Washington’s police department and Georgetown’s law school. The Police for Tomorrow initiative is a two-year fellowship for new recruits that educates them on criminal justice issues such as over-criminalisation, use of force policies and implicit bias.

Brooks’ goal is to “give pause both to those who think police can do no wrong and to those who think they can do no right”. There is more of the former than the latter, but it is worth pointing out that it is still most often the police who receive the benefit of the “complicated narrative” treatment, which is to say, the benefit of the doubt. The powerless seldom receive this benefit. The powerful, always.

The words that have lingered with me, though, are the ones from Brooks’ dedication: “For the men and women of the DC Metropolitan Police Department, who do what we ask them to do.”

Tangled Up in Blue: Policing the American City by Rosa Brooks, Penguin Press, $28, 384 pages

Claire Bushey is the FT’s Chicago reporter

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