Ethics experts say Mick Mulvaney, the White House budget director and interim head of the Consumer Financial Protection Bureau, should be investigated for potentially violating federal bribery laws.

Mulvaney admitted Tuesday that, as a congressman, he only gave meetings to lobbyists who donated to his campaign.

Norm Eisen, a former top ethics official under President Barack Obama, said the FBI should investigate whether Mulvaney's actions in Congress were directly influenced by campaign contributions.

Ethics experts say Mick Mulvaney, the White House budget director and interim head of the Consumer Financial Protection Bureau, should be investigated for potentially violating federal bribery laws after he admitted that, as a congressman, he only gave meetings to lobbyists who donated to his campaign.

Speaking before 1,300 financial industry executives at the American Bankers Association conference in Washington on Tuesday, Mulvaney encouraged the officials to use their money to influence policymaking.

"We had a hierarchy in my office in Congress," said Mulvaney, a former lawmaker from South Carolina, according to The New York Times. "If you're a lobbyist who never gave us money, I didn't talk to you. If you're a lobbyist who gave us money, I might talk to you."

Norm Eisen, a former top ethics official under President Barack Obama, told Business Insider that Mulvaney "better hope that he never went beyond selling access."

Eisen said the White House official should be investigated for possibly engaging in a quid pro quo, in which individuals or groups donated to his campaign in exchange for specific actions he took in his capacity as a lawmaker.

"If I were at the Department of Justice, I'd send an FBI agent to start looking at correlating the lobbyist donations," Eisen said. "I would have the FBI look at his decision-making right up to the present, correlate it with lobbyist campaign contributions, and then go talk to him."

Richard Painter, President George W. Bush's top ethics lawyer, told Business Insider that Mulvaney's admission that he exchanged money for access "puts a target on his back."

As a congressman, Mulvaney received $63,000 in campaign contributions from payday lenders, and since taking over at the CFPB he has loosened regulations on the payday lending industry, which has been accused of engaging in predatory practices.

Earlier this year, Mulvaney ended the CFPB's investigation into a South Carolina-based lender, World Acceptance Corporation, that donated $4,500 to Mulvaney's congressional campaigns, The Times reported.

"The lobbyists are not there to make small talk, they go see officials like Mulvaney to get official action," Eisen said.

Mick Mulvaney, the director of the Consumer Financial Protection Bureau Win McNamee/Getty Images

A high bar for conviction

Ethics and legal experts point out that the legal threshold prosecutors must reach in order to convict a public official of bribery is high.

The evidentiary bar was raised after the Supreme Court's June 2016 decision in McDonnell v. United States, in which it unanimously overturned a former Virginia governor's public-corruption conviction, reigning in what Chief Justice John Roberts called the government's "boundless interpretation" of federal bribery laws.

Prosecutors now must now prove beyond a reasonable doubt that an official took specific actions in exchange for a bribe, illustrating an obvious quid pro quo.

"The evidence stinks to high heaven, but it's very hard to prove," Painter said of Mulvaney's case, adding that Mulvaney's admission makes him "morally unfit for public office."

Many argue that regardless of whether Mulvaney engaged in any illegal conduct, his Tuesday admission is a fireable offense, and excusing it perpetuates a culture of impunity in Washington.

"It is the perfect picture of all that is wrong with DC — and that will remain wrong with DC, even after this administration is gone," Lawrence Lessig, a Harvard professor and former Democratic presidential candidate, told Business Insider in a statement.