Andrew Weissmann, the lead prosecutor for Special Counsel Robert Mueller, has a history of questionable conduct. But the full extent of Weissmann’s alleged prosecutorial misconduct is unclear because some of the most serious charges were hidden behind redactions and secreted in sealed court filings.

Two months ago I sued to have these records released, but late Friday federal Judge Sim Lake’s case manager confirmed that several of the sought-after documents are missing from the court record.

In early November, Houston attorney Kevin Fulton of the Fulton Law Group filed a motion in a Texas federal court to unseal and unredact court records related to claimed prosecutorial misconduct by Weissmann during the latter’s stint as the head of the Enron Task Force.

In a joint motion to dismiss the criminal charges filed against them, four individuals connected to the Enron collapse alleged that Weissmann had improperly threatened witnesses to keep them from speaking with defense lawyers. In support of their motion, the defendants included an email Weissmann had sent to the lawyer of a “critical witness.” What exactly Weissmann said, though, is unclear, as the brief redacted the details:

Even if cause originally existed to keep the content of this email secret, with the underlying criminal cases now complete, there is no longer a basis to hide the details from the public. Thus, my motion to unredact the public record asked Judge Lake, who had presided over the criminal cases, to release unredacted copies of several court filings, most significantly the joint motion to dismiss, which included this email and other relevant details.

Over the holidays, though, the court entered an “amended notice,” announcing that after “a full and exhaustive” search by the clerk, certain court filings “were unrecoverable in their original or un-redacted form,” including the unredacted copy of the joint motion to dismiss and the supporting memorandum. Also missing from the court record was the government’s unredacted response to this motion, which likely would have included the full text—or relevant portions—of the Weissmann email.

Additionally, in the amended notice the court stated that it could not find in the case records the unredacted copy of the declaration made by Michael Tigar, an expert witness who averred that in his 40 years of experience trying criminal cases in state and federal courts, he had never seen such “unfair pressures brought to bear on the adversary system in a single case.” Several of Tigar’s other conclusions, however, were hidden behind redactions.

Finally, the court stated that “Docket Entry No. 568: Sealed Document” was missing from the record. But the subject matter of that sealed document is completely unknown because the public docket does not even list Docket Entry 568.

Upon learning that these documents were missing, Fulton’s firm contacted the court to request that the clerk, if he had not yet done so, contact the clerks of the Fifth Circuit Court of Appeals and the U.S. Supreme Court. After all, the underlying Enron cases involved multiple defendants and several trips to the Fifth Circuit and Supreme Court. When a case is appealed, the record is transmitted to the higher court, then later returned to the district court. So it seemed reasonable to think that during one of the trips back and forth, the relevant portions of the record were inadvertently retained by the appellate court.

However, late Friday it became clear that the records are gone for good, when Judge Lake’s case manager informed the Fulton Law Group that in addition to conducting a “full and exhaustive search of the Houston Division’s records,” search requests had been “made with the Supreme Court, the Fifth Circuit Court of Appeals, and the National Archives,” and those four records were unrecoverable.

The Department of Justice also does not have copies of the records, having told Judge Lake after conducting its own review that it was unable to locate physical or electronic copies of the records. The DOJ then moved for access to the court’s records, which Judge Lake granted.

There is no excuse for these records to be missing, even with the lapse of time. The judiciary maintains court records years after convictions are final, and has detailed procedures to track the location of the files, with the staff responsible for maintaining the records documenting who transferred what to whom, and when, and what was returned, by whom, to whom, and when. Also, in this case the district court still held a majority of the documents requested—so many, in fact, that after receiving four thick binders full of records, the DOJ filed a second motion for an extension of time to reply to the motion to unredact the documents.

To be clear: These facts do not suggest that Weissmann or others on his behalf “disappeared” the records. Nor does any blame lie at Judge Lake’s door. (A federal judge isn’t involved in such logistical matters.) Rather, the most likely scenario is sloppiness by a staffer, but whose staffer—Lake’s, one of the Fifth Circuit judge’s, a Supreme Court justice’s, or one in the clerk’s office or file room—is unlikely to ever be known.

Now we also may never know exactly what transpired when Weissmann oversaw the Enron prosecution. “The third branch of government functions best with proper oversight,” attorney Fulton stressed, upon learning that the records no longer exist. “Unfortunately, the ‘unrecoverable’ court records now hamper that oversight and leave unanswered important questions that the public deserves answers to.”

Efforts to obtain the remaining documents continue, though: By the end of January the DOJ must respond to the motion to unredact the records that haven’t gone missing. The remaining documents, however, are unlikely to provide additional insight into Weissmann’s questionable conduct in the Enron case, which I previously detailed at length here.

Consequently, Weissmann will likely remain Mueller’s “pit bull,” because without the missing documents prompting a public outcry, nothing is likely to change—especially since Mueller led the FBI at the time of the Enron prosecutions and was surely well aware of Weissmann’s modus operandi when he brought him on board as his lead prosecutor. It is facts like these that lead many on the right to question the integrity of the special counsel probe.