Sen. Lindsey Graham, R-S.C., vowed Sunday to launch a thorough inquiry into Democrats on the Senate Judiciary Committee to find out whether there was any wrongdoing in how they managed the sexual misconduct allegation Christine Blasey Ford leveled at Supreme Court nominee Brett Kavanaugh.

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"We're going to do a wholesale, full scale investigation of what I think was a despicable process to deter it from happening again," Graham said during an interview on ABC News' "This Week."

"The FBI will do a supplemental background investigation, then I'm going to call for an investigation of what happened in this committee. Who betrayed Dr. Ford's trust? Who in Feinstein's office recommended Katz as a lawyer? Why did Ms. Ford not know that the committee was willing to go to California?" Graham continued, referring to Sen. Dianne Feinstein, D-Calif., and Debra Katz, one of Ford's attorneys who has been involved in Democratic politics in the past.

President Trump mocked Feinstein, the top Democrat on the Senate Judiciary Committee, at a rally in West Virginia on Saturday for saying last week her staff did not leak a confidential letter Ford sent her local congresswoman, Rep. Anna Eshoo, D-Calif., in July accusing Kavanaugh of sexual assault in the 1980s when they were in high school.

Ryan Grim, the journalist from the Intercept who first reported on the letter, said on Twitter last week that he did not receive it from Feinstein's staff.

Trump also said he hoped an FBI probe into Ford's claims, which will delay the Senate's consideration of Kavanaugh's confirmation by a week, uncovers who leaked the letter to the press.

Graham added Sunday that he accepted Feinstein's denial.

"All I can tell you is it came from somebody with a political motive," he said. "No friend would do this to Dr. Ford."