After years of polarizing and petty politics, we have finally come to this: The “world’s most deliberative body” could grind to a halt over a non-public letter from an anonymous person containing unspecified allegations against a Supreme Court nominee — about his high school years. It appears Democrats have possessed this letter since the summer, from a reported law professor who does not want to be identified. However, critics are demanding answers and a delay in the vote on nominee Brett Kavanugh.

With an expected vote on his nomination only a couple weeks away, Sen. Dianne Feinstein (D-Calif.) issued a statement that she had forwarded a letter to the FBI detailing possible sexual misconduct by Kavanaugh in high school. The last-minute allegations instantly brought to mind the confirmation of Justice Clarence Thomas, who faced a last-minute allegation from a former aide, law professor Anita Hill, of inappropriate sexual comments.

The analogy to the Thomas hearing is obvious and inescapable. Democrats were frustrated in their effort to paint Thomas’s views as outside the legal mainstream — the same strategy used four years before, in 1987, to block Robert Bork. Thomas, however, was selected in part due to his lack of a record in any published articles or remarks. Worse, he refused to answer core questions. The hearing’s lowest moment came when he was asked about his views on Roe v. Wade. Thomas said he really had not thought much about Roe — a statement as unbelievable as it was unresponsive. Nevertheless, he had sufficient votes for confirmation when NPR’s Supreme Court correspondent, Nina Totenberg, received a leaked Judiciary Committee/FBI report on Hill’s allegations. It was a classic “he said, she said” scandal that played out on national television. Thomas would be confirmed, but the country remained divided on whether he or Hill or both were lying.

The Kavanaugh hearings are different in one respect from the Thomas hearing: Kavanaugh has one of the longest, most detailed records of any modern nominee. The problem is that the Republican majority implemented an unprecedented level of restrictions over material, including a virtual blackout of material from when Kavanaugh served as White House secretary under former President George W. Bush. Many other documents were slapped with “Committee Confidential” status to prevent their public use.

Democrats had a legitimate objection to the percentage of withheld documents and the restrictive process imposed by the Republican majority. However, they lost that moral high ground in a series of missteps, from Sen. Cory Booker’s (D-N.J.) self-proclaimed “Spartacus Moment” to Sen. Kamala Harris’s (D-Calif.) misrepresentation of a statement by Kavanaugh about “abortion-inducing drugs.” Moreover, Democrats seemed to engineer confrontations over secret material by not requesting its release before the hearing.

In the end, the Kavanaugh hearings hit a new low in the lack of substantive discussion. The most damaging thing to emerge was Kavanaugh’s habit of putting ketchup on spaghetti. While that should be worthy of a denial as a culinary crime, the hearing was little more than Democratic posturing met by Republican platitudes.

Kavanaugh finished the hearings without a lethal wound. In the meantime, despite his obvious hostility to the interpretive rationale underlying Roe, senators including Susan Collins (R-Maine) and Lisa Murkowski (R-Alaska) appeared willing to vote for him solely on the basis of his referring to Roe as “settled law.”

That is when we suddenly started to hear about “the letter.” Feinstein was publicly attacked over her restrained performance as the ranking Democrat on the Senate committee, and then over holding on to the letter sent to her by Rep. Anna Eshoo (D-Calif.) about allegations made by a law professor. Despite reportedly holding a teaching position at a law school, this professor did not want to be publicly identified. Indeed, Feinstein said the “individual strongly requested confidentiality, declined to come forward or press the matter further, and I have honored that decision.” This leaves Democrats with a letter from someone who is reportedly recounting an incident from decades ago who presumably never made a formal charge, does not want to make a formal charge, and does not want to be identified or “press the matter further.”

If there was a serious offense by Kavanaugh, even as a high school student, we should know about it. His accuser would be entirely protected in bringing forward a credible allegation and, indeed, many would view her as obligated to do so if she is a law professor. Moreover, she is represented by Debra Katz, a leading lawyer in the “MeToo” movement. It is unclear why she would send a letter and retain an attorney, yet refuse to make an allegation on the record or to move forward after raising the issue. However, due to the leak and referral, the allegations are being discussed globally in the media.

This presents a situation far more unfair than the one faced by Justice Thomas.

Thomas was accused of improper conduct as a high-ranking federal official. He faced someone who was willing to be identified and to appear as a witness; he could and did respond to detailed allegations from someone who made her claims in public, on the record.

Kavanaugh faces an unstated allegation from high school, from an unnamed person who does not want to be identified despite reportedly giving the information to Congress.

In addition, this information reportedly was received in July — yet Democrats waited until two weeks before a Senate vote to leak its existence. If they were truly concerned about a victim or underlying sexual misconduct, why would they sit on the letter until now?

As Feinstein must have anticipated, the FBI has declined to open up a criminal allegation of an incident that allegedly occurred decades ago in high school. It simply sent the information to the White House.

I have been critical of the Kavanaugh hearing, and I do not agree with Judge Kavanaugh on various constitutional issues, including his troubling deference to executive power and privileges. However, there needs to be a modicum of decency and fairness in this process. Tossing anonymous, undetailed allegations over the transom shortly before a vote is a new low. Democrats have succeeded not just in losing the high ground but in bulldozing it flat with this attack.

The high ground in Washington always has been measured in millimeters, but it is getting harder and harder to discern, as politics chases the last residue of principle from the process.

Jonathan Turley is the Shapiro Professor of Public Interest Law at George Washington University. You can follow him on Twitter @JonathanTurley.