Fox News’s Laura Ingraham, which aired Thursday, Attorney General William P. Barr insisted that the Russia investigation was “one of the greatest travesties in American history,” a declaration that revealed either troublingly limited knowledge of the past or distressingly unchecked bias.

Worse, the attorney general is matching words with actions. Last year, he ordered an investigation of the Russia investigation, run by U.S. Attorney John Durham. On Thursday, he assured Ms. Ingraham that Mr. Durham would not just produce yet another report on the Russia probe, but also “bring to justice people who were engaged in abuses,” raising the prospect that those involved would be “prosecuted.”

Mr. Barr insisted that federal officials started the Russia investigation “without any basis” and that errors investigators subsequently committed were not “mistakes or sloppiness,” but reflected “something far more troubling.” Their motive, according to Mr. Barr: “to sabotage the presidency.” Intended or no, the message to Justice Department officials now and in the future is: Think twice about ever again investigating a presidential candidate, even if there is good reason to do so, and even if that good reason is the interference of a hostile foreign actor in a U.S. election.

On that issue and others, Mr. Barr clashes with the facts and the record, as carefully laid out, among others, by Justice Department Inspector General Michael Horowitz, who delved into the Russia probe’s origins and conduct and released his own report last year.  FBI had material that “reasonably indicated activity constituting either a federal crime or a threat to national security, or both, may have occurred or may be occurring,” and that there was enough to examine at least four Trump campaign officials. “We did not find documentary or testimonial evidence that political bias or improper motivation influenced the decisions,” Mr. Horowitz noted.

The inspector general did find problems with the subsequent surveillance of Trump official Carter Page, which was based on a special Foreign Intelligence Surveillance Act (FISA) warrant. But Mr. Horowitz released last month  finding that investigators’ misuse of the FISA warrant process was not limited to their probe of the Trump campaign, finding widespread problems with FISA warrant applications unrelated to the Russia probe. While disturbing for other reasons, it poured more cold water on the notion that federal officials targeted President Trump for investigative abuse.

In considering why Mr. Barr continues to argue otherwise, it is hard to determine which possibility is worse: that the attorney general is cynically toeing Mr. Trump’s line to stay in the president’s good graces, or that he really believes the things he says.