Washington (CNN) Attorneys for Christine Blasey Ford sent a letter to FBI Director Chris Wray on Thursday expressing regret that investigators did not speak with her in their review of Supreme Court nominee Brett Kavanaugh.

"The 'investigation' conducted over the past five days is a stain on the process, on the FBI and on our American ideal of justice," read the letter from attorneys Debra Katz, Lisa Banks and Michael Bromwich.

The letter said the FBI "failed to interview" Ford, who alleges Kavanaugh sexually assaulted her during their high school years. Kavanaugh has denied the allegation, and senators received the results of the FBI review into Kavanaugh on Thursday.

Ford appeared before the Senate Judiciary Committee last week where she testified about her allegations against Kavanaugh after coming forward publicly earlier last month.

The attorneys said the FBI also did not interview witnesses with information relevant to Ford's allegations, and in their letter, they provided a series of suggested witnesses who they said were still available to speak with investigators.

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