It was a little after 1 A.M. last Friday morning when the person who has since become known as “the naked man” was briefly detained by police as they searched for Dzhokhar Tsarnaev in the streets of Watertown. By 3 A.M., it was clear that he was not, in fact, connected to the Boston Marathon bombings—he was merely someone who had the misfortune of being in the wrong place at exactly the wrong time. So why has he become a magnet for conspiracy theories?

The answer has to do with the chaos of that night, beginning with the murder of the M.I.T. police officer Sean Collier around 10:30 P.M. Two hours later, with M.I.T. still on lockdown and police still blanketing the area, a twenty-six-year-old Chinese entrepreneur known only as “Danny” told police he’d been carjacked by two men who had driven off in his Mercedes S.U.V. A few minutes after that, two suspects—one of them in a Honda sedan, the other in a Mercedes S.U.V.—began firing on a cop just north of Watertown’s Arsenal Mall. As more police arrived, a quiet residential street turned into a war zone, complete with homemade grenades and hundreds of rounds of ammunition. (The Watertown resident Andrew Kitzenberg has some of the only photographs of this battle.) One of the two suspects was injured and apprehended during that shoot-out, but the other escaped. Undetonated explosives were recovered at the scene, but nobody knew if the missing suspect had more on him, or whether he was wearing a suicide vest. At the time, it wasn’t even known for sure if the two suspects were, in fact, the Tsarnaev brothers. They could have been, for example, other accomplices travelling with them.

This chaos and confusion was only amplified by the number of people on the ground: I counted officers from at least a half-dozen different agencies, including Watertown, Newton, Cambridge, and Boston police; the Massachusetts State Police; and the M.B.T.A. Transit Police. It seemed to me that many were unsure who was in charge.

This, then, was the situation when police found a young man with dark-brown hair alone in a car. They shouted at him to “keep your fucking hands where they are” before putting on flak jackets. Several appeared to arm themselves with sniper rifles. At 1:15, there were shouts and scuffling, followed by barked orders to “drop your underwear” and “get on your hands and knees.” (A CNN cameraman, Gabe Ramirez, was able to capture some grainy footage of the naked suspect being loaded into a police cruiser.) At 1:20, the report went out over the air: “We have a second suspect in custody, we need an I.D. that it’s him, we’re not sure it’s him.”

Twenty-five minutes later, a man who appeared to identify himself as a friend of this “second suspect” was also handcuffed and questioned by police. I tweeted a picture of that person at 1:45 A.M. along with a quote from one of the officers at the scene: “He’s got shit in his pockets. Get down that street now!”

At around 2:30 A.M., the Massachusetts State Police spokesman David Procopio walked over to the press scrum and said that two suspects had been “accounted for,” apparently confirming that both of the Tsarnaev brothers had been apprehended. A half hour after that, just before 3 A.M., he walked over to revise his statement: “One more suspect at large—the two accounted for should be revised. One accounted for, one at large.”

By the time the sun rose the next morning, Tamerlan Tsarnaev had been identified as the person captured during the 1 A.M. shoot-out—he died shortly thereafter—but, somehow, Dzhokhar Tsarnaev was still at large. The two men who were briefly detained in the middle of the night appeared to be all but forgotten to authorities. They were a footnote in a terrifying, tumultuous manhunt that would shut down Boston and its surrounding suburbs. (When I asked a Boston Police Department spokesman about their identities, he referred me to the F.B.I.; an F.B.I. spokeswoman referred me to the Watertown police; and I’m waiting to hear back from the Watertown lieutenant handling media inquiries.)

But once the fact of their existence had been set loose on the Internet, they became two more data points for conspiracy theorists to latch onto. On Sunday, someone associated with Press For Truth, a Canadian outfit dedicated to “expos[ing] the elite and their agenda for a New World Order,” claimed that the Tsarnaevs’ aunt was positive that the naked man was Tamerlan Tsarnaev. (On Thursday, the Tsarnaevs’ mother said the same thing during a news conference.) This, in turn, was used to further all sorts of outrageous notions, some of which were mutually contradictory: the Tzarnaevs were double agents; the bombing was a “false flag” attack staged by the government as part of its ongoing campaign to create a police state; the bombing was faked and the victims and first responders were actors; marathon organizers knew about the attack beforehand.

The fact that the naked man hasn’t been identified only adds to the sense of mystery and intrigue. (Until this morning, when the Boston Globe published a riveting account of the ninety minutes Danny spent with the Tsarnaev brothers, there were those who believed the carjacking victim and the naked man were the same person.) Even if some intrepid reporter does track the naked man down, the morass of conspiracies surrounding the marathon bombing and the twenty-four hours that culminated in Dzhokhar Tsarnaev’s capture last Friday night are not about to disappear; one of the hallmarks of conspiracies is that evidence used to knock them down is interpreted by true believers as proof that they actually exist. But anyone who doesn’t consider himself an Infowars soldier can rest assured that the naked man was just a random guy, who was unlucky enough to look like a suspected terrorist—and lucky enough not to end up seriously hurt.

Seth Mnookin is the co-director of MIT's Graduate Program in Science Writing. You can follow him on Twitter @sethmnookin.

Photograph: Still from YouTube video of Boston police officers taking "the naked man" into custody.

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