An investigation into sexual misconduct allegations against Supreme Court Justice Brett Kavanaugh by multiple women found that no witnesses could provide evidence to substantiate their claims, a letter to Senate Republicans from the Senate Judiciary Committee chairman said Friday.

According to the 414-page report released by Sen. Chuck Grassley, R-Iowa, investigators interviewed more than 40 people, monitored social media and news reports and reviewed evidence provided by the judge and his accusers.

“Following the separate and extensive investigations by both the Committee and the FBI, there was no evidence to substantiate any of the claims of sexual assault made against Justice Kavanaugh,” the report states.

“Following the separate and extensive investigations by both the Committee and the FBI, there was no evidence to substantiate any of the claims of sexual assault made against Justice Kavanaugh.” — Report by Senate Judiciary Committee

The sexual misconduct allegations came during the committee's hearings to decide whether Kavanaugh, whom President Trump nominated in July to succeed retiring Justice Anthony Kennedy, would be confirmed. Kavanaugh's nomination set off a battle between Republicans, most of whom defended the judge, and Democrats, who pushed for a large-scale investigation into the women's allegations.

Among those questioned, the report said, were Mark Judge, PJ Smyth, and Leland Keyser, the three individuals whom accuser Christine Blasey Ford claimed were present in the house when Kavanaugh allegedly threw her on a bed and sexually assaulted her sometime in the 1980s.

Grassley last month requested that the FBI investigate accuser Julie Swetnick and her attorney, Michael Avenatti, who also represents porn star Stormy Daniels in her allegations against President Trump. Swetnick’s credibility was questioned after an ex-boyfriend told Fox News that "she exaggerated everything" and threatened to kill his unborn child.

TRUMP CHALLENGES DEMS AFTER KAVANAUGH ACCUSER ALLEGEDLY ADMITS TO MAKING FALSE RAPE CLAIM

Investigators found no evidence to support either woman’s claims. Swetnick also made several contradictory statements about her claims during television interviews and refused to speak with committee investigators, the letter said.

“Indeed, the evidence appears to support the position that Julie Swetnick and Mr. Avenatti criminally conspired to make materially false statements to the Committee and obstruct the Committee’s investigation.”

“Indeed, the evidence appears to support the position that Julie Swetnick and Mr. Avenatti criminally conspired to make materially false statements to the Committee and obstruct the Committee’s investigation.” — Chairman Chuck Grassley, Senate Judiciary Committee

Other alleged incidents involving Kavanaugh, said to have occurred in three states, were found not to be credible.

Grassley also requested an investigation into Judy Munro-Leighton, who anonymously claimed Kavanaugh slapped her and forced her to perform oral sex on him.

KAVANAUGH ACCUSER REFERRED TO DOJ FOR FALSE STATEMENTS, GRASSLEY'S OFFICE ANNOUNCES

Munro-Leighton contacted the committee in October claiming she wrote an anonymous letter accusing the judge of sexual misconduct. Grassley said she later recanted authorship and admitted to not knowing Kavanaugh under questioning from the committee.

“She later admitted that she was not the author of it and merely used it as a “ploy” to “get attention” and had never met Justice Kavanaugh,” according to the letter.

In September, President Trump ordered a limited FBI probe into allegations by Ford and accuser Deborah Ramirez.

The investigation found no evidence of wrongdoing on Kavanaugh’s part.

Fox News' Gregg Re and the Associated Press contributed to this report.