The information Christopher Steele was providing so perfectly fit into a narrative of conspiracy that it was impossible to ignore, and almost too good to check.

It’s called “falling in love with your source.” I did it, my colleagues did it, intelligence professionals collectively do it, and none of us are ever the better for it.

Here’s how it happens, at least from the collector level. I spent 20 years in the U.S. Army as an interrogator and strategic debriefer, with most of my second decade of service spent in and around embassies in the Middle East. My job at the embassy was to debrief walk-in sources, defectors, visa applicants of particular interest who agreed to talk to me, and anyone else of interest to the intelligence community who popped up in the region and fell into my column as a debriefing subject.

I dealt with thousands of sources, most of whom occupied a brief hour or two of my time, and whose information met a standing need for basic intelligence on Iraq. Others, particularly walk-ins or defectors with potentially valuable information to share, took days or weeks to thoroughly and appropriately debrief. Their information was usually of much greater significance to the IC than the standard fare, and it made the work much more satisfying for the debriefer.

Engaging in an extended debriefing series with a source who knows information that could enhance or change our collective understanding of tier-one national intelligence requirements is heady. If doing a market-basket debrief of an Iraqi visa applicant was a mid-week Major League Baseball day game in July, conducting a series of debriefings on a troubled member of a terrorist cell, a regime-hating microbiologist, or a defecting government official was a World Series game.

To borrow from FBI agent Peter Strzok’s terminology, it mattered. Thousands of consumers watched closely, and it was an opportunity to excel.

This close attention meant that, unlike a less-important debriefing, you’d be receiving volumes of analysis and feedback almost in real time. If you published your report at the end of the day in the Middle East, the intelligence community (IC) would just be waking up, and would spend their day critiquing and analyzing the information you published. The results of their analysis greeted you when you logged on the next morning, and guided your next session, conducted while Washington slept.

It’s Hard to Manage This Attention Well

Professional interrogators and debriefers will tell you that a major challenge of their job is to remain agnostic about the information the source relays. Their job is to use whatever skills they have to determine if the source’s comportment is consistent with someone telling the truth, to recognize and counter attempts to evade or deflect questions, and to faithfully report all information collected, regardless of their personal opinion of its veracity.

They call it raw, unevaluated intelligence for a reason: the interrogator collects it, and the analysts assess its veracity. Whatever issues you may have with the source’s credibility are worked out in the room, through thorough, methodical questioning and unrelenting follow-up. While there’s little room on a standard Intelligence Information Report for editorializing, a responsible debriefer will notify headquarters of his or her opinion of the source’s veracity, and will note significant red flags and behavioral issues in the “Reporting Officer Comments” section of the report.

I say all of this to tell you that the worst possible scenario for a debriefer engaged in an extended series of interviews with a subject is to fall in love with the source. By “fall in love” I mean to allow your excitement at the possibility that what he is telling you is true to overcome your responsibility to recognize, counter, and report red flags and blinking lights that may suggest your source is being less than forthcoming, or even lying.

You don’t want this to be the case. The last thing you want to hear from analysts after a session in which you believed the source was telling you the truth was that he was lying to you, and, by the way, here’s the reporting that proves you were duped. It’s soul-crushing. You question your skills, you’re embarrassed to have vouched for the guy, and you wonder if you’ve lost your edge.

But This Happened with the FBI and Christopher Steele

The FBI fell in love with their source. The information Christopher Steele was providing so perfectly fit into a narrative of collusion and conspiracy by the Republican presidential candidate and his staff that it was impossible to ignore, and almost too good to check. They tried to check it—desperately, I would guess—yet, according to those who have read the four separate Foreign Intelligence Surveillance Act (FISA) packets on Carter Page, they were never able to verify the information he provided.

There are two paths available when facing this situation. You can either dump your source and alert the intelligence community of your inability to verify the source’s information, or you can ignore the flashing red lights and rationalize the inconsistencies.

This information made sense, after all. It was explosive, it was sensational, and it was damning. If it was true, the ramifications—to the election, to the Trump team, to the nation, and to the FBI—were mind-boggling. To again paraphrase Deputy Assistant Director Strzok, we’re talking impeachment here.

U.S. agencies chose the second path. The FBI and DoJ decided that their “love” for their source overcame their inability to validate his information, so they decided that vouching for the source would supersede their responsibility (and inability) to verify the information. “We couldn’t independently validate the information, but we can represent to you with confidence that our source has been, and is, credible. We therefore are certifying that the information in that dossier is credible.”

As I said, this never ends well. Those lights flash for a reason. Steele’s denial of interactions with the media; freely expressed hatred for the target of the dossier; admitted inclusion of unsolicited and uncorroborated information in the dossier; the prevalence of easily debunked allegations—professional intelligence collectors ignore flashing lights like these at their peril.

In this case, they ignored them at the peril of Page, an American citizen with alleged connections to shady Russian characters who may or may not have attempted to convince him to enter a collusive, cooperative relationship. According to every FISA expert available to our cable news networks, the FBI was obligated to provide only corroborated, validated information to the FISA court in seeking a probable cause ruling that this American citizen was an agent of a foreign power.

The Desire Was So Deep, It Led to Concealment

The FBI succeeded in obtaining that ruling—four times—using, as a central part of their case, the uncorroborated information provided by a source with whom they were deeply, hopelessly in love. They wanted to believe him, so they ignored his warts and imperfections. They wanted the judge to love him as much as they did, so they hid those warts and imperfections from the court.

Embarrassed about the true story of the circumstances of how they came to meet, they hid their initial interlocutor’s baggage in a vague, speculative word salad. They believed their relationship was too important to allow the dubious agenda of those who introduced them to tear them apart. They’d moved on from that and were in a good place. The judge didn’t need to be bothered with those messy details.

When they discovered Steele had been seeing someone else, that he was cheating on their relationship by entering a series of illicit liaisons with just about every national newspaper (and a number of government agencies) in town, they had no choice but to break it off. But they couldn’t quit him completely. While they eventually informed the judge when and why they’d parted ways, they failed to note that they continued to communicate through a friendly mediator. They still had issues to work through.

If You Can Only Trust Him Partly, It’s Time to Get Out

I’ve been burned by sources, multiple times, each of which has left a scar that reminded me to be more careful in assessing the intent of the next person sitting across the table, seeking my interest and approval. Each time it happened, the end came through the intervention of a concerned friend—an analyst at headquarters telling me that I was being taken for a ride, and showing me proof that I was either being lied to, or that the story I was being fed couldn’t be validated.

To acknowledge that they may have been wrong all along was all too hurtful.

Not once did headquarters choose to ignore the blinking red lights and push on with the relationship, hoping that maybe something he was telling me was true. It never happened, and never should happen in a professional intelligence operation. It doesn’t matter that 10, 25, or 50 percent of the source’s information may be credible. It’s the remaining percentage of inaccurate information that defines the value of the relationship and requires an intervention. If you can only trust your partner 50 percent of the time, it’s time to get out of the relationship.

Unfortunately, as is often the case with affairs of the heart, when challenged by others on his indiscretions, the FBI chose to focus on Steele’s good side—the side that supported their suspicion that Trump and his associates were deeply involved in collusive relationships with Russian intelligence agents. They also hid his bad side—the side that would provoke a suitably informed judge contemplating secret action against an American citizen to ask more questions, or demand more proof, before granting the warrant to spy on Page.

To acknowledge that they may have been wrong all along was all too hurtful. It would have reflected more on the FBI’s judgement than on Steele’s reporting. They couldn’t bring themselves to accept that it wasn’t him, it was us.