The murder of Democratic National Committee staffer Seth Rich in the summer of 2016 remains unsolved, still under investigation by police in Washington, D.C. It is the inspiration for round after round of baseless speculation about the cause of his death, linking it to the leak of thousands of Democratic Party emails that year. And those theories are generating yet another lawsuit.

This week, Aaron Rich, Seth Rich's brother, sued Dallas financial adviser Ed Butowsky, a pivotal figure in early coverage of the case, along with a conservative conspiracy theorist and the The Washington Times. The suit alleges that the trio promoted groundless accusations about Aaron Rich's involvement in the leaks of those emails to Wikileaks.

There is no publicly known factual basis for making those accusations. U.S. intelligence and national security officials under both the Obama and Trump administrations concluded that hackers acting at the behest of the Russian government had illegally hacked the Democratic National Committee emails.

Aaron Rich's lawsuit is the third related to politically motivated conspiracy theories about Seth Rich's death filed against Butowsky, a sometime Fox News contributor.

The claims about Seth Rich were the core of a Fox News story last May — retracted a week later and the subject of a lawsuit filed by Rich's parents against Fox News filed earlier this year. Butowsky had allegedly been a key figure in orchestrating that story, according to material contained in a lawsuit filed last August against Fox News, Butowsky and a Fox News reporter stemming from that same discredited Fox News story. (Fox News said the story had not been subjected to sufficiently rigorous editing and scrutiny but did not apologize to the Riches.)

Aaron Rich's attorneys point to additional public statements from Butowsky and an online conservative activist named Matt Couch (along with Couch's company, America First Media) that they claim strongly imply Aaron Rich engineered the mechanics of getting the Democratic Party emails to WikiLeaks and that he accepted money from the shadowy outfit.

"Aaron wants to clear his name," Rich's attorney, Michael Gottlieb, told NPR. "The accusation is that he's conspired with a hostile foreign intelligence service to steal documents from an American political organization in exchange for money. ... It's completely and utterly fabricated and baseless."

As a candidate, President Trump hailed Wikileaks for publicizing the Democratic emails, which showed dissension within the Democratic Party over Hillary Clinton's primary battle with Bernie Sanders. Trump's CIA chief, Mike Pompeo, has called WikiLeaks a hostile intelligence service.

According to the lawsuit, filed this week in federal court in Washington D.C., Aaron Rich holds security clearance for the work he does for a defense contractor. Gottlieb says his client views the accusation of helping WikiLeaks as tantamount to an accusation of treason.

In commenting on the lawsuit, Butowsky told NPR he was merely repeating what Rich's parents told him about Aaron Rich during his first call to the couple, back in December 2016. Butowsky claims that Joel Rich said he knew his sons had been involved in downloading those documents for WikiLeaks in exchange for payment — a contention that a spokesman for Aaron Rich's family and his attorneys heatedly deny.

On March 18, The Washington Times published an opinion piece by a retired commander in chief of the Pacific fleet, James A. Lyons, titled, "More Cover Up Questions." It linked Seth Rich's death to the leaked emails and cited Butowsky as a source. (Lyons and Butowsky had served together on an unofficial "citizens' commission" on the deadly attack on the U.S. mission in Benghazi, a touchstone for conservative critics of the Obama administration.)

Senior executives at The Washington Times did not return NPR's calls seeking comment.

The lawsuit documents what it says is coordination between Butowsky and Couch; it presents evidence that Butowsky is seen weighing in during one of Couch's live streaming Periscope video commentaries to say that WikiLeaks payments to Aaron Rich were "confirmed" by his parents.

In remarks this week to NPR, Butowsky affirmed the exchange. He told NPR it was the only public online discussion he had with Couch.

Butowsky further distanced himself from Couch in speaking to NPR: "I don't really know Matt at all. I have talked to him from time to time," Butowsky said. "But I don't really know what's credible or who's credible." He pointed back to what he alleged are the December 2016 remarks from Aaron Rich's parents (which they reject).

Butowsky told NPR that he is currently representing himself in the case because, he said, he considered it ridiculous.

In another Periscope streaming video posted after the lawsuit was filed, Matt Couch said he would not be deterred in his search for the truth. Couch cited Butowsky for his claims. Couch has raised money off his theories, asking for donations through PayPal. He claims the donations will help him solve Seth Rich's murder and show the connection between the killing and the WikiLeaks postings.

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