Even as there appears to be no hard evidence supporting Higgins’ and Johnson’s theory, and very little support for it outside the authors of the document, it is having alarming, real-world effects. At least one member of Congress whom Higgins says he briefed about the theory appears to have parroted its contents on television. And, as with conspiracy theories that have arisen in other national tragedies, from 9/11 to Sandy Hook, the Vegas theory has caused measurable damage: the Higgins and Johnson report, which was posted online anonymously earlier this year, goes so far as to name an individual they allege was Paddock’s accomplice and had “possible ties to Islamic organizations and possible Islamic State linkage.” That man, Brian Hodge, an Australian native based in Los Angeles who was at the Mandalay Bay on the night of the shooting, spoke with me—and vehemently denies any involvement. He also told me the attention he has gotten from Higgins’ and Johnson’s claim—their report contains detailed personal information about him—has led to death threats and strangers showing up at his home. “It’s been a living nightmare,” Hodge told me by phone.

What’s also alarming about this particular conspiracy is that it’s being driven by people who not long ago held senior positions in the intelligence community and who still have access to members of the government. One day in late September, Higgins texted me via Signal: “I was told by a fairly senior former official that the Bureau has placed everyone knowledgeable on Vegas under a gag order with threats of polygraphs. Even formers have been told, ‘Shut the fuck up’.” In other words, the government, Higgins claimed, wasn’t allowing officials to follow up on his and Johnson’s supposed leads. I don’t know if this is true. What’s clear is that Higgins’ very ties to a network of intelligence officers, analysts, agents and contractors have fed into his conspiracy theories—and reinforced his and Johnson’s determination to stay on the case, with little regard for the consequences.