Charisse Jones

USA TODAY

As the spotlight on law enforcement grows ever harsher, from the sex scandal roiling the Oakland Police Department to the corruption web enveloping the NYPD to the numbing tick-tock of black men killed by the police, the perspective of a top cop — a black cop — makes one sit up and take notice.

In his memoir Once A Cop (Atria, 308 pp., *** out of four stars), Corey Pegues, who rose to deputy inspector in the New York Police Department before leaving the force in 2013, gives us an incisive look at life on both sides of the blue line.

Pegues has straddled multiple worlds since he was a child growing up in Queens. He was a teenage crack dealer who was also a popular high school basketball player. As a police officer, he felt a connection to the residents of the underprivileged communities he often patrolled, unlike many of his peers. He was a black man who endured racism and resentment from some white officers, but enjoyed the friendship and respect of more than a few as well.

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That duality gives Pegues a nuanced perspective of the often-fractious relationship between communities of color and law enforcement. He feels, for instance, that New York's controversial stop-question-and-frisk policy could be useful, but was abused as a result of political pressure. He believes most officers want to do a good job and get home safely rather than engage in confrontation.

Yet Pegues also recounts his own feelings of powerlessness when he was a rookie manning a police rally, and watched some of his fellow officers topple barricades and aim racial epithets at David Dinkins, New York’s first black mayor. “Police can’t police police,’’ he writes of the memory.

Apart from the most publicized instances of police brutality, “the real problem, the real frustration, is the day to day,’’ he says. “There’s an arrogance about the way a lot of cops treat minorities.’’ And Pegues reveals his own complicated relationship with the NYPD. Saying he was harassed because of his activism, Pegues filed suit against the department, The New York Post and Nassau County for race discrimination, defamation and other allegations.

Once A Cop is not all police work. There are riveting glimpses of a different sort, as Pegues reminisces about the golden age of hip-hop in Queens, home to Run DMC, LL Cool J and other rap luminaries in all their Kangol-wearing glory. Those vignettes are fleeting. There could have been more.

But perhaps Pegues felt at this moment in America it was more important to relay his experiences wearing a badge. To that end, his example is a somewhat hopeful one.

When Pegues became a lieutenant, he forbade his officers from sending those arrested for offenses such as turnstile jumping to central booking simply because they did not have an I.D. — an act that was not a crime, but because of the booking process led to arrest records for people who were often young, black or brown.

He wanted to protect as well as serve. "The power not to arrest someone,'' he writes. "That power lies 100% with the police officer — and that’s a lot of power for one person to have.’’