Hieronymus “Harry” Bosch has become one of the great figures in contemporary American mystery fiction, and this ethical, tough-but-softhearted Los Angeles policeman has brought enormous, well-deserved success to his creator, Michael Connelly.

Driven to protect the good people of his city and to put away the bad guys, Bosch is haunted by every case he can’t solve and by every killer or rapist he can’t catch. He’s the cop we would want on the case if something bad happened to someone we love. This stuff doesn’t just come out of the ether; it comes from the author’s own mind, and from his heart. Mr. Connelly knows what is right and its converse, and so does the character who, to some degree, reflects the character of the author.

Since Bosch got his first name partially from Harry “Dirty Harry” Callahan, you know the punks he encounters are in for a hard day when they smugly point out that they have more rights than Captain Ahab’s sock drawer.

What a surprise, then, when Mr. Connelly wrote “The Lincoln Lawyer,” about a defense attorney, Mickey Haller, whose job it was to set loose the same hoods, thugs, and other lower forms of life whom Bosch worked so hard to put behind bars, and even made Haller a sympathetic character.

If you read “The Lincoln Lawyer” (and if you haven’t, please see a therapist immediately, as you need serious and urgent help) you will recall that Haller is a somewhat less-than-successful attorney who does most of his work from the backseat of his Lincoln Town Cars — not because he can’t afford an office, exactly, but because Los Angeles County has 40 courthouses spread over its 450 square miles and there can be no more efficient way of covering them when the problems of his various clients require different venues.

In the just released “The Brass Verdict” (Little, Brown, 405 pages, $26.99), Haller is back, and so is — perhaps inevitably, as they work in the same criminal justice system in the same city — Bosch.

Haller, a moral defense attorney (yes, the word “oxymoron” leaps to mind), works on the understanding that, as he says,

Everybody lies. Cops lie. Lawyers lie. Witnesses lie. The victims lie. A trial is a contest of lies. And everybody in the courtroom knows this. The judge knows this. Even the jury knows this. They come into the building knowing they will be lied to. They take their seats in the box and agree to be lied to.

Haller believes his job is to be “the truth in a place where everybody lies.”

After a couple of difficult years, good fortune strikes in a stunning manner. Jerry Vincent, a former colleague, is murdered and has named Haller to inherit his client list, most notably the lucrative case of Walter Elliot, the executive of a movie studio who has been accused of murdering his wife and her lover.

Elliot proves to be a difficult, noncooperative client with a boatload of secrets, and Haller’s frustration mounts as he tries to find the evidence that will set his client free. It becomes increasingly clear that someone will do whatever is needed to prevent this from happening. Vincent appears to have been killed because he learned too much and as Haller digs deeper, hunting for the clue that he is convinced cost Vincent his life, he finds himself in peril of the same fate.

As Bosch investigates the murder, he develops a plan to get the killer to raise his head: Offer bait. Offer Haller.

Bosch and Haller are related in more ways than just as two men on opposite sides of the criminal justice system. In the second novel about Bosch, “The Black Ice,” he learned that he had a half-brother, Mickey Haller, and circumstances finally bring them together in this superb novel.

Even in the context of what is probably the finest legal system in the world, things do not always work as they should. Haller’s greatest fear is defending an innocent man. No lawyer wants an innocent man on his conscience if things go wrong.

Sometimes the system cannot seem to dispense the justice that society desires and needs. That is when someone may decide to ignore the rules and dispense simple street justice. It is delivered with a bullet. It is what cops call “the brass verdict.”

Mr. Penzler is the proprietor of the Mysterious Bookshop in Manhattan and the series editor of the annual Best American Mystery Stories. He can be reached at ottopenzler@mysteriousbookshop.com.