A top Senate Republican released an investigation Tuesday that concluded Los Angeles Mayor Eric Garcetti “likely knew or should have known” that a former top adviser was allegedly sexually harassing city employees, a finding that appears to contradict the mayor’s assertion that he was unaware of any inappropriate behavior.

A 23-page report released by U.S. Sen. Chuck Grassley of Iowa said his office’s investigation found it was “extremely unlikely” that the Democratic mayor, who was nominated by President Joe Biden to serve as ambassador to India, would not have been aware of the misconduct allegations against his former aide, Rick Jacobs.

The White House issued a statement saying Biden had confidence in Garcetti and called on the Senate to confirm him.

“This partisan report was a hit job from the beginning, and many of the claims have already been conclusively debunked by more serious independent reports,” said the statement by spokesman Chris Meagher. “It repackages allegations already addressed under oath and does not interview key participants.”

The report marks the latest development in Garcetti’s effort to fill one of the nation’s most prominent diplomatic roles. The nomination has been languishing in the Senate since July, as the mayor faced questions about what he knew, and when, regarding the allegations against Jacobs.

At a Senate Foreign Relations Committee hearing in December, Garcetti told senators considering his nomination that he never witnessed Jacobs sexually harass one of his police bodyguards, allegations that are at the center of a lawsuit filed against his administration.

The lawsuit charges that Jacobs frequently sexually harassed the police bodyguard while Garcetti ignored it or laughed it off. The mayor has repeatedly denied the claims. Jacobs has called the allegations of misconduct “fiction.”

Grassley disclosed the investigation in March, saying he had received “numerous credible allegations” that Garcetti was aware of the sexual harassment but did nothing to stop it. At the time, he said he could not vote to confirm Garcetti, saying the nation deserved an ambassador who will “represent the values of the United States.”

Investigators interviewed 15 witnesses, read 26 depositions taken in the lawsuit and consulted other materials, including emails and text messages. The report said Garcetti and Jacobs declined to be interviewed.

Much of the evidence cited in the report has previously been made public. However, one apparently new account involves a whistleblower who allegedly saw Jacobs at the U.S.-China Climate Summit in 2015 sexually harass an employee who was working on a laptop, including pressing his groin area on the person’s back. Senior staffers later laughed it off, the report said.

“Investigators believe this allegation is credible because it fits the pattern of behavior described by several other senior staff members in Mayor Garcetti’s office, and because of its similarity to allegations” in the lawsuit, the report found.

In a statement, Garcetti spokeswoman Dae Levine said, “No new facts were uncovered in this report and Mayor Garcetti strongly reaffirms the simple truth that he never witnessed or was made aware of sexual harassment.”