A copy of the 568-page report by Justice Department Inspector General Michael Horowitz after its release in Washington on Thursday. (Jim Bourg/Reuters)

Harry Litman teaches constitutional law at the University of California at San Diego. He served as deputy assistant attorney general in the Justice Department from 1993 to 1998 and U.S. attorney for the Western District of Pennsylvania from 1998 to 2001.

The report released Thursday by the Justice Department inspector general on events leading up to the 2016 presidential election distributes blame across many quarters for improper conduct by the department and the FBI. Michael Horowitz, the inspector general, found much to criticize in the actions of both the most senior officials — notably then-FBI Director James B. Comey and then-Attorney General Loretta E. Lynch — as well as line investigators working the criminal probe of Hillary Clinton.

Horowitz blasted Comey for departing “clearly and dramatically” from FBI and department norms in Comey’s public announcements concerning the Clinton email probe. While Horowitz, importantly, found that Comey’s improprieties were not the result of political bias, he nevertheless concluded that “the decisions negatively impacted the perception of the FBI and the Department as fair administrators of justice.”

Horowitz likewise took Lynch to task for her tarmac meeting with former president Bill Clinton when the investigation against Hillary Clinton was in full throttle: “Lynch’s failure to recognize the appearance problem created by former President Clinton’s visit and to take action to cut the visit short was an error in judgment.”

And Horowitz leveled especially hard-hitting charges of misconduct against Lisa Page and Peter Strzok, two FBI officials (and, at the time, romantic partners) on the Clinton email investigation and, until their misconduct surfaced, on the Robert S. Mueller III investigation. Horowitz found that the two exchanged text messages “that potentially indicated or created the appearance that investigative decisions were impacted by bias or improper considerations.”

This and similar conduct by five FBI employees, he concluded, “demonstrated extremely poor judgment and a gross lack of professionalism” and merited a referral to the FBI to determine whether there had been violations of the FBI code of conduct.

All in all, a pretty rough report card — one that does not reflect well on Justice or the FBI. Yet it is important to keep in mind: Nothing in the report undermines the legitimacy of the ongoing Mueller probe, as Trump partisans seem poised to claim. If anything, Comey’s misconduct in particular could only have helped Trump.

But Team Trump has signaled that its strategy is to leverage the report into a general attack on the reliability of Comey as, in Trump’s words, “an untruthful slime ball.” As Trump lawyer Rudolph W. Giuliani put it: “We want the concentration of this to be on Comey versus the president’s credibility, and I think we win that and people get that.”

Critically, however, nothing in Horowitz’s report has anything but tangential bearing on Comey’s credibility. In particular, it does not undercut Comey’s veracity in his accounts of his discussions with Trump, in which, according to Comey’s contemporaneous memos, the president tried to get him to drop the investigation of national security adviser Michael Flynn.

As for the fairly scathing criticism of Strzok and Page, it also does nothing to call the Mueller probe into question. After the pair was removed from the investigation, any work they had done was the subject of a careful independent review. In any event, what matters is ultimately not the probity of Strzok and Page but of Mueller, who dealt swiftly with the issue once it was discovered.

There is a larger, more important point here. The inspector general is an integral part of a department dedicated to principled conduct and accountability. When credible allegations of professional misbehavior arise, the inspector general works to resolve them, and his determination is not subject to overruling by the attorney general or any other political actor.

As for Horowitz himself, he is a straight shooter who has earned his reputation for credibility and steadfast independence throughout a career of politically fraught assignments.

Which brings us to the irony: In Trump’s worldview, where all law enforcement is thinly disguised political partisanship and the Justice Department the political arm of the party in power, a body such as the inspector general would not exist, much less be overseen by an honest broker such as Horowitz. For that reason, it’s good to take the opportunity of the inspector general’s report to call out again the heinous lie, and the corrosive effect, of Trump’s “deep state” diatribes.

None of which, of course, will stop the president and his supporters from trumpeting vindication from the Horowitz report. For now, though, Trump partisans and antagonists alike assert that the department speaks the truth. The black eyes to Comey and the FBI reflect fair blows from an honest public servant, however they are used — or misused — by political partisans.