U.S. Sen. Chuck Grassley, R-Iowa., has formally requested updates from the Department of Justice (DOJ) and FBI on four criminal referrals submitted last year of individuals who fabricated allegations against then-Judge Brett Kavanaugh.

In a letter written to Attorney General William Barr and FBI Director Christopher Wray Tuesday, Grassley is giving the DOJ and the FBI 13 days to provide Congress an update on what the agencies did with the Senate Judiciary Committee’s referrals one year after their submission.

“Investigations in support of the judicial nomination process are an essential part of the constitutional role in confirming judges,” Grassley wrote, who was chairman of the Judiciary Committee when the referrals were made. “It is important to protect the constitutional process from being hijacked by bad actors involved in insidious partisan operations.”

The letter was signed by each Republican member of the committee at the time of the referrals except for then-Sen. Ben Sasse, R-Neb.

Grassley’s request comes a year after the Supreme Court saw one of its most polarizing confirmation battles with Brett Kavanaugh replacing Justice Anthony Kennedy, who retired in summer 2018.

Prior to his nomination to the nation’s highest court, Kavanaugh served as a highly respected judge on the U.S. Court of Appeals for the District of Columbia. Yet his confirmation battle was rife with controversy due to several unsubstantiated and discredited claims of sexual assault that were alleged to have occurred more than three decades ago.

The most prominent charge of sexual misconduct lobbied against Kavanaugh came from Christine Blasey Ford, who was unable to demonstrate that she had ever met Kavanaugh, much less that he had assaulted her. Blasey Ford’s father told Kavanaugh’s father he was glad the justice was confirmed, which indicated his serious doubts about his daughter’s story.

Further, none of the four witnesses that Ford named corroborated Ford’s story, including her lifelong friend Leland Keyser. Keyser was pressured to change her testimony to say something more supportive of Ford’s claims, but declined to do so.

Throughout the confirmation process, the Senate Judiciary Committee investigated multiple other charges accusing Kavanaugh of sexual misconduct and made four criminal referrals to federal law enforcement agencies of witnesses who admitted to making false claims. The referrals include attorney Michael Avenatti and his client Julie Swetnick, who claimed that Kavanaugh ran a serial gang rape cartel through the suburbs of Maryland when he was a young teenager, and Judy Munro-Leighton, who confessed to fabricating a story submitted to the office of Sen. Kamala Harris, D-Calif., claiming that Kavanaugh raped her.