The man himself is the opposite of his books: modest, quietly spoken and polite. It is difficult to imagine him emitting an expletive, let alone carrying in his mind the scenes of degradation and uncontrolled violence that form the basis of his work.

Yet I am not alone in believing that Pelecanos is becoming one of the great chroniclers of American society. His patch is Washington DC, the part that the tourists and the politicians rarely bother with, far from the White House and Capitol Hill.

Pelecanos’s Washington is peopled by the disadvantaged, the vulnerable and the criminal. His novels teem with drug dealers, prostitutes, pimps, conmen, grifters, shady businessmen, enforcers, petty gangsters and gunmen — and their victims. Then there are the cops and private detectives, good and bad, Pelecanos’s main characters, if not always his heroes.

The Night Gardener, Pelecanos’s 14th novel, introduces two new cops. In 1985 Gus Ramone and Dan Holiday were junior detectives on the homicide squad, investigating a series of murders of black teenagers whose bodies were found in a community garden. Their names were palindromes – Eve, Ava and Otto. The mystery was never solved. Twenty years later, another body is discovered in the same circumstances. The victim’s name is Asa.

Ramone knew him. Holiday, who left the force under a cloud and became a hard-drinking, sexist and racist security adviser, reappears, as does the sergeant who led the inquiry, now sick but still haunted by his failure to bring the killer to justice.

“I identified with Ramone,” Pelecanos says. “I wanted to write about a guy who had a family, what he was like at home. And that veered into the territory of my own life.

“The cliché is the cop who is obsessed with his cases, can’t have a normal family life, he’s divorced, turns to drink and so on. I worked with a lot of cops, the homicide police, before I did this book. There are all sorts. There are some guys whose lives are falling apart. But there are others who go home at night and do all these normal things and leave the work behind.”

Like most of Pelecanos’s books, The Night Gardener doesn’t end with a pat solution. “In most crime fiction, a murder is committed in the first chapter and solved in the last. I don’t do that. That’s not what happens in real life. In DC the majority of homicides are never cleared up.”

Pelecanos’s novels paint a portrait of a dysfunctional society — with drugs and guns out of control, racial prejudice rampant, and politicians unable or unwilling to provide remedies.

I tell him that I know of no white writer so comfortable with black characters, of whom there are many, both low-life and heroic. He replies that the parts of Washington he writes about are three-quarters black; it would be dishonest to ignore that. He deals with race not as a problem, but as a fact, including tensions between black and white.

“You’ve got to let the characters speak honestly, even if it makes the audience uncomfortable. I want to make them uncomfortable. When you put the reader off balance, it’s not a big prescription for success.

“The smart thing to do is to make people feel good about themselves and say to them at the end of the book, it’s going to be all right, there’s no such thing as racism, we’re all the same deep down inside. I won’t do that.” But he shies away from grandiose answers.

“I don’t have a solution. But I do like to show that one person can make a difference to somebody’s life. Just one person — whether a teacher, sports coach or cop. It’s very important that I show that. A teacher, for example, turned me on to books. I really wasn’t going anywhere. I had no plans and no way to get there. I took a class and one guy set me on a path. Had I not walked into that room and taken that class there’s no question that I wouldn’t be here, I’d be working in a bar somewhere.

“I see it all the time in the city, quiet heroes working with kids. You can’t say let’s legalise drugs or let’s fix the schools by throwing more money into them. That’s not the answer. The answer’s one by one.”

Pelecanos’s first novel came out in 1992 when he was 35 and there has been one a year since. He’s not yet 50, so he could end up with 25 or more novels to his name. They will all be about Washington. He has no desire to move himself or his novels elsewhere. They will cover many eras and many social truths. The comparisons made by some reviewers with Zola and Balzac may not seem so far-fetched.

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