“God’ll Cut You Down” by John Safran (Riverhead Books, 351 pages)

When John Safran undertook the stunts that fill his first book, he was famous enough in Australia to have filmed a documentary series called “John Safran’s Race Relations.” Part of the process led him from Melbourne to Mississippi to look for bigots. It wasn’t hard for him either to find or to caricature white supremacists, and he zeroed in on 67-year-old Richard Barrett, whose claims to fame included both founding the American skinhead movement and now sporting a comb-over.

But why Richard Barrett specifically? “My researcher shot off emails to a dozen Klan types,” Safran explains in “God’ll Cut You Down,” the book he decided to squeeze out of the unexpectedly complicated Barrett story, “and he’s the one who got back to us.”

Safran’s credentials as a pest and prankster are quickly established when he sneaks a DNA sample from Barrett, has it analyzed and then makes a speech at a rally for white patriots and athletes that Barrett takes pride in hosting. Here’s a sample of how grating Safran can sound: “Um, well, thank you to the people of Mississippi and, um, congratulations to all the, er, participants in the Spirit of America Day awards.” He drops the affected hemming and hawing when it’s time to announce what the DNA has revealed: that Barrett the racist has a soupcon of African blood.

Barrett threatened criminal charges. Safran’s Australian network refused to air the program. And Safran would have had nothing more than a gag reel for his archives had Barrett not been brutally murdered in 2010 by someone who stabbed him multiple times and then set fire to his house. A young black man, Vincent McGee, was accused and convicted of the killing. Supposed motive: McGee’s anger at being underpaid for maintenance work Barrett had hired him to do.

But the situation was so full of unanswered questions that it brought out Safran’s inner Truman Capote. So he came back to Mississippi, this time to try his hand at writing a true-crime book.

By the time he begins investigating the crime, Safran has toned down his case of the cutes, at least a little; we still have to hear about each time he pulls his Flip video camera out of his pocket to film an interview, and to read chapter subheadlines such as “More Than One Way to Skin a KKKat.” We also have to go along with the false pretense that Safran is breathlessly making discoveries page by page, even though the book sounds as if it were written well after the events it describes actually occurred. And he has been indulged to include such would-be charming asides as: “I lick the Cheetos dust off my fingers. I flap my hands to dry them. I don’t want Cheetos dust on my keyboard.”

This stalling is used to disguise a couple of central issues about the Barrett case: Mississippi is a more complicated place than Safran supposed it was, and bigots’ private lives don’t necessarily align with their public pronouncements. In Barrett’s case, the opposite was true: He had strong homoerotic feelings toward black men and had acted on his attraction to McGee, according to Safran’s dogged reporting. The accused’s claim that he killed Barrett over being paid about $20 for a day’s maintenance work never took into account how much more Barrett would pay him for other kinds of services.

“God’ll Cut You Down” does tap into rich veins of prejudice and hatred. They’re just not the ones for which Safran had prepared himself. He seems totally agog at the notions of a black teenager with a troubled family history or a white man who has spent most of his life living alone and furtively, emerging only to make the occasional hate speech, mingle with politicians or ogle handsome young athletes.

In the past, Safran’s specialty seems to have been cheap, easy gags that aim to infuriate, as when he arranged to switch Palestinian and Israeli sperm bank samples. But he’s in way over his head with the strange new types of rage and self-denial that emerge here.

This would be a much better book if its lightweight author dared to venture outside his comfort zone. But it’s much easier for him to describe his haggling with McGee over payoffs than it is to delve into how and why this young man became capable of such brutality. His original, cliched idea of the black suspect as an innocent victim makes for an easy opening assumption. But it eventually must give way to abundant evidence of Vincent McGee’s turbulent past and reckless, self-defeating path to the killing.

And it’s easier for Safran to pigeonhole Barrett as a pathetic joke than it is to understand how such an odd character found more acceptance in rural Mississippi than he might have in a place where folks were nosier. Everybody seems to have had an idea what Richard Barrett’s proclivities were like, but nobody saw fit to interfere with him. This clashes radically with the author’s initial idea of Mississippi as a benighted police state. Though he sustains a veneer of jokiness, it’s clear that he winds up thoroughly flummoxed.

He puts it best: “In Mississippi, the more layers of the onion I peel, the more I’m standing in a mess of onion.”