A document filed Wednesday, apparently by accident, by lawyers defending former Trump campaign chairman Paul Manafort appears to show that the source for an Associated Press story detailing payments to Manafort’s firm by a pro-Russia Ukrainian political party was also a confidential source for Special Counsel Robert Mueller’s probe.

The document may be part of an intended effort by Manafort’s defense to claim that investigators improperly collaborated with the media, a popular (and regularly debunked) right-wing talking point. But it appears to show only that prosecutors and the AP relied on the same source — something that’s not that surprising.

“The suggestion that AP would voluntarily serve as the source of information for a government agency is categorically untrue,” Lauren Easton, the director of media relations for the AP, told TPM.

The document mentions two memos from Manafort to Rinat Akhmetov. Akhmetov is among Ukraine’s wealthiest men and a key ally of Vladimir Putin. It says the Manafort memos were “received by Maloni from AP.” That suggests that the Associated Press showed the memos to Manafort spokesman Jason Maloni for comment.

The document then says: “In the Winter of 2017 (sic 2016) employee of DMI –CS-1 permitted the reporter to view material on a hard drive copy of DMI’s electronic files.”

That suggests that AP’s source at Davis Manafort, referred to in the document as “DMI,” was also a confidential source (“CS1”) for Mueller’s investigation.

The document refers to an April 2017 AP story that suggested, based on Davis Manafort records, that the firm had received at least $1.2 million payments from the pro-Russian Ukrainian political party, the Party of Regions.

In October, Mueller charged Manafort with conspiracy against the U.S., conspiracy to launder money, acting as an unregistered agent of a foreign principal, and false and misleading FARA (Foreign Agents Registration Act) statements. The FARA violations are unusual — prosecutions under that law are vanishingly rare.

Manafort’s team has in the past complained of overreach by Meuller’s office, the FBI and the Department of Justice (DOJ). In a lawsuit filed earlier this month against Mueller, Manafort’s lawyers called the charges against the lobbyist “completely unmoored from the Special Counsel’s original jurisdiction.”

Maloni declined to comment to TPM.