One of the women who accused Supreme Court Judge Brett Kavanaugh of sexual assault has apparently admitted she lied and used the allegations as a "ploy" to get attention.

Charles Grassley, the chairman of the United States Judiciary Committee, has sent a letter to US Attorney General, Jeff Sessions, and the FBI, asking for an investigation into Judy Munro-Leighton.

According to the letter, Ms Munro-Leighton fabricated documents to pose as a Jane Doe who had previously contacted Senators alleging Judge Kavanaugh of sexual misconduct and assault.

The Jane Doe from Oceanside, California sent a letter to Senator Kamala Harris on September 25 alleging that Judge Kavanaugh and a friend raped her in the backseat of a car.

The letter influenced the committee's questioning of Judge Kavanaugh on September 26 and in response to the letter, he said "The whole thing is ridiculous… the whole thing is a crock, farce, wrong, didn't happen, not anything close".

The committee then publicly released a transcript of the interview and the letter.

On October 3, three days before Judge Kavanaugh was to be sworn in, Ms Munro-Leighton reached out to the Senate Judiciary, which was investigating the letter, claiming to be the Jane Doe and repeating the allegations. Her email to the committee included a version of the anonymously-written letter.

Following an investigation into the woman, the committee reportedly found she was a "left-wing activist" who is "decades older than Judge Kavanaugh" and lives in Kentucky, not California.

After being confronted with the results of the investigation, Ms Munro-Leighton admitted she had not been sexually assaulted by the Judge, was not the author of the Jane Doe letter, and said she had done thing whole thing for attention.

"I did that as a way to grab attention. I am not Jane Doe… but I did read Jane Doe's letter. I read the transcript of the call to your Committee… I saw it online. It was news," the letter said Ms Munro-Leighton admitted.

She allegedly also said the accusations had been a "tactic" and a "ploy" to oppose Judge Kavanaugh's nomination.

Mr Grassley said the false allegations had had severe implications for the Committee's investigation into the numerous allegations against Judge Kavanaugh, including spending many resources on trying to track the woman down.

While he said the committee was "grateful" for any citizens coming forward with information, misleading the committee and diverting their attention during an already time-sensitive investigation was serious, and "potentially illegal".

"It is illegal to make materially false, fictitious or fraudulent statements to Congressional investigations. It is illegal to obstruct Committee investigations," said Mr Grassley.

He asked the Attorney General and FBI to investigate Ms Munro-Leighton in relation to these charges.

The Jane Doe allegations were only one of many accusations against Judge Kavanaugh.

Christine Blasey Ford testified against the man, accusing him of assaulting her and other women when they were in college.

Despite her efforts to block his nomination, Judge Kavanaugh was appointed the newest Justice.

Newshub.