The rumor began in the hours after James Holmes killed 12 people and injured 70 more during a 2012 screening of The Dark Knight Rises. Speaking at a press conference in Manhattan, then-New York police commissioner Ray Kelly said that Holmes had actually referred to himself as the Joker. “He had his hair painted red, he said he was ‘the Joker,’ obviously the ‘enemy’ of Batman,” Kelly said.

As the Joaquin Phoenix-starring Joker opens in theaters, talk of the tragedy has made the rounds again, repeated by critics concerned that the new Joker might inspire copycat violence, perhaps because Holmes had allegedly been motivated by the character seven years ago. There’s just one problem with that theory.

“It never happened,” said George Brauchler, the Colorado district attorney who prosecuted Holmes, citing Kelly as the source of the rumor. Brauchler and other Colorado officials have attempted to clarify for years that Holmes never referred to himself as the Joker. The story has persisted, Brauchler said, because it fits the narrative so cleanly. “Of course the crazy-hair-colored guy who shot up the Batman premiere thought he was the Joker, of course!” Brauchler added. “And yet it has no connection to reality.” (Kelly did not respond to requests for comment.)

The potency of the Holmes rumor, regardless of its basis in fact, has made the release of Joker fraught, particularly for Aurora survivors and relatives of the victims. Brauchler said the rumor has become part of the dark lore of the Aurora shooting. “I was in Texas a week or two ago teaching at their statewide conference for prosecutors and I asked, ‘How many people here heard that this guy thought he was the Joker?’ and about a third to half of the hands go up,” he recalled. “It’s four years [after the trial], and these are prosecutors!” It’s a reminder that even in the age of instant fact-checking, we still get hung up on false stories when they’re sticky enough. In a 2015 interview with the Denver Post, he said that his team did not push back on the rumor during the trial because it was focused on getting the death penalty for Holmes (he was ultimately given 12 life sentences, one for each person he killed, plus another 3,318 years). Pressing the issue on whether Holmes fashioned himself after a comic book villain didn’t seem entirely relevant.

However, there have been attempts to set the record straight about Holmes’s dyed orange-red hair, which some considered a potential sign of his Joker fandom (though the Joker‘s hair is dyed green). Dr. William Reid, the psychiatrist who interviewed Holmes for several hours during the trial and later published the book A Dark Night in Aurora, said the shooter had dyed his hair prior to the shooting, after being inspired by a friend who had blue hair.

“When I asked Holmes about him dying his hair red, he said, ‘Well, my friend dyed his blue, so I said I’d dye mine too and I just picked red,’” Reid said, noting that it was seemingly a random choice with no correlation to a comic book character. Reid also asked the murderer outright if he had been inspired by the Joker at all.

“He said that the first he heard of the Joker idea was [from] somebody in another cell,” he said. “He heard calling back and forth, ‘Hey, you’re the Joker,’ or something like that.”