Donald Trump’s decision to hire Rudy Giuliani as his personal attorney appeared to backfire spectacularly on Wednesday night as the former prosecutor veered off script during an interview with Sean Hannity, as Giuliani undercut the president’s public statements on several issues, including his relationship with his longtime lawyer Michael Cohen and the ouster of former F.B.I. Director James Comey. But the most startling disclosure was Giuliani’s assertion that Trump not only knew about Cohen’s $130,000 payment to buy the silence of adult-film star Stormy Daniels about her alleged affair with the president, but that he reimbursed Cohen for the hush money—potentially implicating Trump in a violation of campaign-finance laws.

Giuliani offered the admission unprompted, in response to an unrelated question about the status of the ongoing Trump-Russia investigation. The payment to Daniels, he asserted, would “turn out to be perfectly legal” because the money came out of Trump’s own pocket. “Sorry, I’m giving you a fact now that you don’t know,” he continued. “It’s not campaign money. No campaign-finance violation.”

When Cohen first acknowledged the payment in February, his insisted that the president had no knowledge of it. “I used my own personal funds to facilitate a payment of $130,000 to Ms. Stephanie Clifford,” Cohen said in a statement. “Neither the Trump Organization nor the Trump campaign was a party to the transaction with Ms. Clifford, and neither reimbursed me for the payment, either directly or indirectly.” In March, White House Press Secretary Sarah Huckabee Sanders told reporters that she has conversations with Trump about hush money and “There was no knowledge of any payments from the president.” When Trump himself was asked whether he knew about the $130,000 sum, his response was terse: “No,” he said, adding, “You’ll have to ask Michael Cohen.”

Recognizing that Giuliani had made a potentially damning admission, Hannity offered the former presidential candidate an opportunity to clarify his comments about the payment to Daniels, whose real name is Stephanie Clifford. But Giuliani didn’t take it. “The question there was, the only possible violation there would be: was it a campaign-finance violation? Which usually results in a fine, by the way, not this big stormtroopers coming in and breaking down his apartment and breaking down his office,” Giuliani explained. “That was money that was paid by his lawyer, the way I would do, out of his law firm funds or whatever funds—it doesn’t matter—and the president reimbursed that over the period of several months.” (Giuliani later told The New York Times that the repayment had been made in $35,000 installments, over several months, totaling “$460,000 or $470,000”—an amount, he said, that included “incidental expenses.”)

In a series of tweets Thursday morning, Donald Trump described these payments as “a monthly retainer, not from the campaign and having nothing to do with the campaign.” But legal experts were immediately skeptical of the idea that the arrangement would not have constituted an illegal, “in kind” campaign contribution. According to Federal Election Campaign Act of 1971, a “contribution” is defined as “any gift, subscription, loan, advance, or deposit of money or anything of value made by any person for the purpose of influencing any election for Federal office.” Notably, the money does not need to come from a campaign’s coffers. “If Trump knew that Cohen was advancing him a $130,000 loan for campaign purposes, that would have to be reported by the campaign, as would the payments Giuliani said Trump made in installments to Cohen. These would be campaign expenditures that the committee has to keep track of,” Richard Hasen, a professor of election law at the University of California-Irvine, wrote for Slate.