Rudy Giuliani, President Donald Trump’s personal attorney, revived the baseless Seth Rich conspiracy theory on Twitter by citing a well-known conspiracy theorist. Giuliani also continues to boost Twitter accounts that have pushed another conspiracy theory, QAnon.

On August 26, Giuliani amplified a tweet by Matt Couch, a far-right conspiracy theorist, that had pushed a conspiracy theory about the murder of Democratic National Committee staffer Seth Rich. According to the conspiracy theory, Rich was murdered as part of a cover-up because he was the source behind the leaked DNC emails published by WikiLeaks in 2016. Russian intelligence agents were reportedly partly responsible for planting the story. Authorities have said Rich’s death was the result of a botched robbery, and special counsel Robert Mueller directly debunked the conspiracy theory in the his report on Russian interference in the 2016 election. Right-wing media figures and outlets harassed Rich’s family over the conspiracy theory, and eventually Rich’s brother sued Couch and others for defamation.

Couch again tweeted about the conspiracy theory on August 25, questioning why “they called it a botched robbery and sue anyone who investigates it.” On Monday, Giuliani quote tweeted Couch and wrote, “I’d like to know.”