This week, President Obama told Americans that “we don’t operate on incomplete information.” It was a repudiation of FBI Director James B. Comey’s decision to reveal publicly that his agency was reviewing documents relating to Hillary Clinton’s emails.

The truth, though, is that Comey has a track record of wading into politically charged conversations with little evidence in hand and major consequences in mind. He often undermines his superiors along the way.

Last October, while speaking to an international police chief conference, Comey addressed the “Ferguson effect,” the idea that increased police scrutiny has led to a spike in violent crime because officers are fearful of doing their jobs. Researchers investigated and thoroughly debunked this idea, finding that the increased murder rate in 2015 was predominantly a localized phenomenon and within the range of year-to-year fluctuations.

But even after Obama dismissed the theory for lack of statistical evidence, Comey entered the debate: “The question [is] whether [increased scrutiny is] changing police behavior all over the country,” he said to a room of hundreds of police officers. “The answer is, I don’t know. I don’t know whether this explains it entirely, but I do have a strong sense that some part of the explanation is a chill wind blowing through American law enforcement over the last year. And that wind is surely changing behavior.”

In May, the New York Times reported that Comey brought up this “strong sense” again, saying “that while he could offer no statistical proof of the Ferguson Effect,” he believed after speaking with a number of police officials that a “viral video effect” — with officers wary of confronting suspects for fear of ending up on a video — “could well be at the heart of a spike in violent crime in some cities.” He again admitted that there was no evidence to support a link between violent crime and viral videos, which didn’t stop him from implying, of course, that there was.

And just this October, Comey said in a speech: “In a nation of almost a million law enforcement officers and tens of millions of police encounters each year, a small group of [shooting] videos serve as proof of an epidemic … Americans actually have no idea whether the number of black people or brown people or white people being shot by police is up, down, or sideways over the last 10 years.” In this statement, Comey implied that a lack of definitive data shows that there is no epidemic of police shootings of people of color. For Comey, no matter how little data exists, his own private assessment is enough to draw conclusions.

It’s dangerous for a top law enforcement official to embrace a theory with an underlying assumption that police need to resort to aggressive policing techniques without public scrutiny to do their job. And what makes this line of thinking even more damaging is that the dearth of information on police shootings is in large part due to his own agency’s failure to collect such data in a reliable and unbiased way.  The FBI’s data collection is incomplete: The Bureau of Justice Statistics found that the FBI’s Uniform Crime Reporting Program captured less than 50 percent of homicides by law enforcement in 2003-2011. And the FBI only collects data on killings by law enforcement considered justifiable, so the data being collected, which is presented as objective, is already infused with law enforcement’s own evaluation of the homicide. Collecting and publishing data embedded with the biased judgment of law enforcement creates a false sense of transparency and clouds the inquiry at the outset, much like Comey’s most recent comments to Congress did with respect to Clinton’s emails.

In his letter to Congress last week, Comey once again pleaded ignorance: “the F.B.I. cannot yet assess whether or not this material may be significant.” But his actions (with which his boss the attorney general disagreed) imply that the emails are significant, and to the dismay of Democrats and Republicans alike, the disclosure has had a major impact on the already-in-progress presidential election.

Comey has yet again leveraged his own ignorance into powerful political messaging disguised as transparency. His history of making uninformed, yet substantial statements reveal at their most innocent, a penchant for irresponsible political meddling, and at their most nefarious, an active political agenda.