Seth Rich came to D.C. to pursue a career in politics and last worked at the Democratic National Committee. Rich was shot dead on July 10, 2016. Here is what's known about the murder. (Claritza Jimenez/The Washington Post)

On July 10, at 4:19 a.m., gunfire was detected in the District's Bloomingdale neighborhood. Not five minutes later, police found Seth Rich, a 27-year-old Democratic National Committee staffer, lying on the ground, dying from a bullet wound to his back. A conscious Rich was transported to the hospital; by daybreak, he was dead.

Nearly one year later, Rich's death remains one of America's thousands of unsolved murders — and the focus of endless conspiracy theories, spread this past week by Fox News, alt-right social media, a local D.C. news station and the Russian embassy in Britain. The reemergence of the conspiracy theory this week, which did not lack for real news, revealed plenty about the fake news ecosystem (or to use BuzzFeed's useful phrase, “the upside-down media”) in the Trump era. It also happened to cause untold pain for the Rich family, which has sent a cease-and-desist letter to the so-called private investigator who led this dive back into the fever swamp.

Here's what we learned.

TV news can be an easy mark. This iteration of the Seth Rich story started when the District's own Fox 5 ran a Monday night “exclusive,” citing one source — a Fox New legal commentator, Rod Wheeler — for a “big break in the investigation.” Reporter Marina Marraco reported that “conspiracy theories” could “be proven right,” as Wheeler was saying what had been rumored since last year: Rich might have leaked DNC emails to WikiLeaks, making him the target of an assassination.

“You have information that could link Seth Rich to WikiLeaks?” asked Marraco.

“Absolutely. Yeah. That's confirmed,” said Wheeler, who Fox 5 identified as the Rich family's investigator.

Within 24 hours, reporters at NBC News, CNN and The Washington Post had debunked the story. First, Rich's family quickly corrected the idea that Wheeler was on their payroll; he was hired by Ed Butowsky, a Texas businessman who had grown interested in the case. Next, Wheeler told CNN he hadn't actually obtained information linking Rich to WikiLeaks — Fox 5, he insisted, had told him to say so.

Marraco did not cite any sources except Wheeler — not the Rich family, not D.C. police, not the mayor's office, not the DNC. Wheeler, a very occasional TV pundit, was noticeably skimpy on details, suggesting he had a source who'd told him eyeball-to-eyeball that Rich's computer was in lock-up and that it had evidence of WikiLeaks contact. But he was murky on whether D.C. police or the FBI allegedly had the laptop, and the family quickly reported that neither did.

Most forms of reporting have guardrails that this story would have crashed against. Had the channel waited to run the story until the family or the police weighed in, it couldn't have aired. But that's the problem — there's a fluff allowance on TV, one that lets sensational videos through even if they've not been fully vetted. That's why a quick perusal of local news will often find segments devoted to viral videos, a phenomenon Nathan Fielder tested in an episode of his gonzo series “Nathan For You.”

In retrospect, it seems natural for the fake story to resurface via a small TV station. But what caused it to surface at all?

Fake news has weakened on Facebook, but its bots still own Twitter. With very little fanfare, likely a result of the backlash it got from conservatives after Gawker revealed its editorial policy for newsfeeds, Facebook has seriously cracked down on the ability of conspiracy and clickbait sites to make stories trend.

There's been no similar crackdown on Twitter, where conspiracy theorists can still coordinate, start trends, and benefit when bots chime in. That happened this week, in a big way. The theory that Rich must have been killed by nefarious forces at the Democratic National Committee, as punishment for his betrayal to WikiLeaks, has bubbled long enough to have several memes ready for the latest eruption. Even before the Fox5 segment, the #SethRich and #HisNameWasSethRich hashtag were active; the latest “break” in the story came when Robbin Young, a former model who calls herself a “Bond Girl” on the strength of a small role in “For Your Eyes Only,” published unverified messages that she claimed showed the hacker Guccifer 2.0 crediting Rich for the leak.

The hashtag took off in the wake of the Fox5 report. A familiar swirl of conservative media — the Drudge Report, Breitbart — ran people-are-saying updates on how Rich's name was trending. It was that attention, ironically, that caused Wheeler to be debunked. And it was debunked so quickly that adherents of the theory didn't realize that the new “break” made no sense. Wasn't Guccifer the pass-through for the hacked emails? Why would Rich be contacting WikiLeaks?

The most effective conspiracy theories target both the left and alt-right. What's often forgotten about the DNC hack is how banal the emails were. There were three major hacks of the Democrats' political operation. They were the DNC hack, released by WikiLeaks on July 22 last year; the Democratic Congressional Campaign Committee (DCCC) hack, released on Aug. 12; and the hack of Clinton campaign chairman John Podesta's emails, which were released in a daily dump throughout October. The resignation of DNC chair Debbie Wasserman Schultz during the Democrats' convention fed into the idea that the DNC hack must have been devastating, revealing — in the words of Fox News conspiracy theorist Sean Hannity — that the “DNC was conspiring to hurt Bernie Sanders and help Hillary Clinton win the nomination.”

That's not what the emails revealed. In fact, Wasserman Schultz's mismanagement of the DNC, and personal bias toward Hillary Clinton, had been known, and a sore spot for supporters of Sanders, long before the hack. Wasserman Schultz scheduled debates late in the process, and had to be pushed by the Sanders campaign to allow a debate before the New York primary. Clinton, who'd narrowly lost the 2008 primary, came into 2016 with the vast majority of endorsements from party leaders — not actually a factor under the DNC's control. What the emails found was that in May, after Sanders had no serious chance at the nomination, some DNC staffers got irresponsibly snarky and irritated. On May 1, for example, Wasserman Schultz reacted to news that Sanders would seek to contest the nomination at the convention by writing “so much for a traditional presumptive nominee.”

But by May 1, Clinton had a lead in the delegate count and popular vote that was not going to be outpaced by Sanders, even if he won a landslide in California's looming primary. The theory that Rich was offended by these emails assumes that 1) he saw them, which is not suggested by any of the emails' headers, and that 2) he would have interpreted exasperated emails in May as proof of anti-Sanders perfidy that the world needed to see. This doesn't comport with reality — but it is attractive to the most die-hard progressive foes of Clinton. The Rich conspiracy thrived not just because fringe conservatives liked the idea of a break in the “Clinton body count” theory, but that the idea that someone would murder a leaker to cover up a conspiracy against Bernie Sanders would justify so much angst. Briefly, before Wheeler recanted his story, the Young Turks network's “Jimmy Dore Show” chewed over the revelation that Rich was in contact with WikiLeaks.

And a largely frivolous lawsuit against the DNC — announced in July, and playing out in a Florida court now — has been aggressively covered by the Russian propaganda network RT. (Among the finer points of the lawsuit is that it seeks damages against the DNC for allowing itself to be hacked.) Dore's show has backed away from the story since Wednesday. RT, unsurprisingly, has not.

Debunking a story still doesn't end it. Sean Hannity, who's now a sort of elder statesman in Fox News's prime time lineup, devoted parts of three episodes this week to the Rich story. The first of these episodes ended in a wreck, with Wheeler giving his last public interview to date, recanting much of his story about Rich and babbling about how a credible source told him a story consistent with, perhaps, Rich having emailed WikiLeaks.

Rush Limbaugh, who discussed the story this week, was just as ready to roll over the facts. After playing a clip of the debunked Wheeler story, in which the investigator claimed that authorities were preventing him from probing the Rich-WikiLeaks connection, Limbaugh claimed that the hacked emails had also been locked up. “Nobody has seen the 44,000 emails! They're on this guy's laptop.” But everyone who's wanted to has seen those emails — they have been on WikiLeaks's servers since last year.

The absolute faith that there will one day be proof of this conspiracy theory — proof that Democrats carried out a political murder to punish a leak that had already happened — is impervious to reality. It's bound to attract opportunists. On Saturday, Hannity perked up when he saw the accused copyright violator Kim Dotcom, who is facing extradition, claiming — out of nowhere — that he would break the story wide open.

So: Dotcom, who is facing extradition from New Zealand to America, and who has personally blamed Barack Obama for his legal trouble, claims in May 2017 that he knew crucial details about a political murder from July 2016. Why would he have sat on that during a hotly contested election, one that looked until the last minute to be queuing up Obama's chosen successor?

None of it makes sense. That means we're never going to stop hearing about it.