Democratic National Committee Chairman Tom Perez said Wednesday he only learned days ago about the DNC’s role in the “Trump dossier” that contained salacious claims about President Trump and his ties to Russia.

Perez discussed the dossier during an event at the University of Chicago Institute of Politics on Wednesday, where he was asked if the DNC knew what information was contained in the controversial document.

“Well, again, you’re going to have to ask folks who were at the DNC at that time,” he said.

When he was pressed by interviewer Karen Tumulty of the Washington Post as to how it was possible he didn’t know what was in the dossier, Perez said he only recently learned about it.

“I learned about the dossier a few days ago, OK?” Perez said. “You hire a lawyer, and we hire lawyers all the time who hire third-party vendors to do their work, and so we knew that we were paying for opposition research at the DNC, but we didn’t ask questions about who they were hiring in the context of doing their research.”

“And what we know is that Donald Trump, you know, we had very strong reason to believe that Donald Trump and the Donald Trump campaign and the Russians were potentially conspiring to affect the election for the president of the United States,” he added.

Perez’s comments on the dossier and what he knew about it come two days after the Washington Post reported the DNC and Hillary Clinton’s presidential campaign paid for the research that resulted in the document.

According to the Washington Post, Marc Elias, a lawyer for the Clinton campaign and the DNC, hired opposition research firm Fusion GPS to oversee research into Trump. Fusion GPS then hired Christopher Steele, a former British intelligence officer, who authored the salacious document, which included claims that haven’t been verified.

Fusion GPS had already been conducting research on Trump on behalf of an unidentified Republican client during the Republican primaries. Elias and his law firm, Perkins Coie, hired Fusion GPS in April 2016 on behalf of the DNC and Clinton’s campaign, and continued paying for the research until just before the election.

Following the revelations, the DNC said its “new leadership,” including Perez, wasn’t involved in the decision to hire Fusion GPS.

But Perez said Wednesday he found the hype surrounding the dossier “curious” because campaigns typically conduct opposition research on political opponents.

“I find this issue somewhat curious because, here’s a news flash. Candidates conduct research on their opponents, and in the case of Donald Trump, the imperative for that—to not do that is political malpractice. Why? Because Donald Trump refused to release so many documents,” Perez said.

He also said he was “glad” the research into Trump was being conducted.

“The research centers around whether the Trump administration and the Russians conspired to steal an election,” he said. “That’s serious stuff, my friends. There’s a criminal investigation.”