The Democratic National Committee and Hillary Clinton’s campaign partly funded research that resulted in the controversial dossier alleging ties between President Donald Trump and Russia, the Washington Post reported late Tuesday.

The Washington Post reported, citing unnamed sources familiar with the matter, that Clinton campaign attorney Marc Elias retained research firm Fusion GPS in April 2016 to conduct research into Trump.

Prior to that date, the firm’s research was funded during the Republican primary by an unknown Republican client, according to the report.

The Washington Post reported that Fusion GPS gave research documents and reports by former MI6 officer Christopher Steele, who was not directed by the DNC or Clinton’s campaign, to Elias.

One unnamed source told the Washington Post that Elias’ firm did not inform Clinton’s campaign or the DNC of the research firm’s role.

According to the report, multiple sources told the Washington Post it is “standard practice for political campaigns to use law firms to hire outside researchers in order to ensure their work is protected by attorney-client and work product privileges.”

Clinton’s campaign and the DNC, via Elias’ law firm Perkins Coie, split the cost of Fusion GPS’ research, according to the Washington Post, which the firm continued through the end of Oct. 2016.

A Democratic official told TPM that “it doesn’t matter who paid for the research.”

“What matters is there’s a serious, ongoing investigation into these issues being conducted by the Special Prosecutor and multiple Congressional committees,” the official told TPM.

DNC communications director Xochitl Hinojosa told TPM by email, “Tom Perez and the new leadership of the DNC were not involved in any decision-making regarding Fusion GPS, nor were they aware that Perkins Coie was working with the organization.”

“But let’s be clear,” Hinojosa said. “There is a serious federal investigation into the Trump campaign’s ties to Russia, and the American public deserves to know what happened.”

Trump last week suggested that “Russia, the FBI or the Dems (or all)” could have paid for the document, which he incorrectly claimed was “discredited.”

While many of the claims in the dossier have not been substantiated, a number of the claims it contains have been reinforced by new information.

Lawyers representing Fusion GPS last week asked a judge to block House Intelligence Committee chairman Devin Nunes’ (R-CA) subpoena to the firm’s bank for the identity of the client who commissioned the research leading to the so-called Trump dossier.

This post has been updated.