There are two things I want you to remember when you've finished reading this article: (1) Always film the police, even during what seem to be risk-free, mundane encounters, and (2) always file a complaint when you believe something weird has happened. This is not a waste of time. Logging an official statement of concern in the Seattle Police Department's files creates a record of the incident that can help the department track problem officers. And it has the potential to land the officer in hot water if he or she has done something wrong.

Let me explain: On a chilly night last December, the number of Seattle police officers dwarfed the number of Black Lives Matter protesters who'd shown up for a demonstration at University Village mall. The demonstrators walked through the shopping center singing mournful protest carols about Mike Brown and Eric Garner, two unarmed African American men killed by police whose deaths provoked outrage across the country. I was covering the demonstration. I believe the Black Lives Matter movement is the most important driver of change that can help end the police killings of innocent black people. I also believe it is wrong for police to intimidate nonviolent protesters in any way whatsoever.

There were, at one point, two strange men in puffy jackets standing in the middle of the shopping center. A protester—a college student named Isaac Robinson who'd gotten involved in the Black Lives Matter movement—walked past them and said, "Those guys are definitely informants." The men kept standing there, next to the parking garage, in the freezing cold, not particularly close to the entrance to any store.

Here's what I wrote last December about what happened next:

I approached them, smiling and trying to suggest friendliness, and asked who they were and if they were police informants. One of them asked who I was. I identified myself as a reporter for The Stranger. The shorter man, with whitening hair peeking out from below his beanie, said sneeringly, "Well, I'm a reporter for the New York Times." I began pulling my business card from my pocket and offered to show it to them, but they waved me away. "We don't want to see your business card," the other man said.

One of the men took my photo with his cell-phone camera. I told them calmly I was going to do the same thing and lifted my phone to take the shot. As I did so, one of them deliberately walked straight into me with his elbow jutting out, pushing my body sideways. In that moment, he blocked me from doing my job and taking a photo—a violation of SPD policy, which prohibits officers from interfering with any non-criminal citizens who want to observe and photograph them. It wasn't violent, per se. But it was sudden, unwanted physical contact.

With that, the two men took off across the parking lot and disappeared into a clothing store.

Later in the evening, I spoke to Claire Sullivan, another demonstrator. She said a middle-aged man with a beard had approached them from behind during their march. "I thought he was taking pictures of the bike cops, but then I realized he was taking photos of us," Sullivan said. When she asked the man for his name and badge number, having come to the conclusion that he was an undercover police officer, she said he "straight-up bolted."

Nikkita Oliver, a leader in the local Black Lives Matter movement, said the presence of these strange men hovering around "causes people who want to exercise their rights to be on edge, and can automatically cause fear and distrust of the police."

"If these men were undercover police," I wrote on The Stranger's blog, Slog, the following day, "they were also three other things last night: unprofessional, awkward, and not very good at their jobs."

Sean Whitcomb, an SPD spokesperson, wouldn't confirm or deny that they were local police officers. He said they could have been private security guards or from another law enforcement agency. But he also remarked, "Cover blown is a big deal." And he suggested I file a complaint with the Office of Professional Accountability (OPA), which investigates police misconduct.

I did, and eight months later, after the OPA's investigation was complete, I learned that Robinson, the Black Lives Matter protester who first pointed the two men out to me as possible "informants," was right to be suspicious. It turns out those two unidentified men, who Robinson thought were feeding information to the police, were the police.

We only know this because after the December protest, I went online to and filled out a complaint form. The next month, SPD sergeant Tyrone Davis e-mailed me and asked that I come into the OPA's office, on the 18th floor of a nondescript downtown office building, for an interview.

OPA director Pierce Murphy has made much of the fact that the agency moved out of SPD headquarters in 2013, finally extricating itself from the same building that houses the police leadership and signaling its independence. But the office feels antiseptic and remote from the street level, which is where most people have run-ins with police. (It ought to be a storefront that feels welcoming and encouraging to people who may be scared or mistrustful of police. There ought to be "Know Your Rights" posters on the wall. Instead, the walls have artsy photos of mounds of dirt or salt.)

In a room splitting off from the hallway, Davis placed a recorder on the table, had me explain what happened, and asked some probing questions. He seemed to find it hard to believe that I'd actually filed a complaint about this—didn't I understand that if these men were undercover police, they wouldn't want to be identified under any circumstances? But Davis wasn't hostile. We continued to talk, and I stood by what happened.

Murphy rightly wants to use civilians, not police officers, for these intake interviews. But he's waiting on the city's negotiations with the Seattle Police Officers' Guild (SPOG) to be able to make that change.

I didn't hear anything about my OPA case after that and, frankly, forgot about it—until July 28, when an e-mail from Murphy appeared in my inbox: "Case Completion Notice OPA #2015-0052."

In my "Case Completion Notice," the OPA confirmed that the strange, rude, skittish men in puffy jackets were Seattle police officers.

Murphy, in a letter addressed to me, said they were "plainclothes" officers. (The department prefers the word "plainclothes" to "undercover" for describing officers who are trying—and sometimes failing—to blend in and not be noticed. "Undercover" officers, in the department's nomenclature, are officers who are deliberately adopting the identity of someone else. But the popular term is "undercover," so I'll keep using it here.)

"You had every right to contact, observe, and/or photograph the two plainclothes SPD officers standing in a public place," Murphy said. But because of their assignment, he said, they weren't required to identify themselves or engage with me in any way.

Still, any use of force in that situation, no matter how small, was prohibited. The officer was not allowed to push me.

"Both you and the named employee agree there was physical contact made between you as the two officers turned to walk away," Murphy explained. "However, you did not agree on whether it was you or the named employee who walked into the other. You believe the contact was an intentional act by the named employee, while the named employee described it more as inadvertent contact caused by your movement.

"While I find your account more plausible than that of the named employee," Murphy concluded, "there was insufficient evidence to form a preponderance in support of either account."

Murphy issued a "Not Sustained (Inconclusive)" finding on the undercover officer's alleged misuse of force against me. But he also advised SPD to better train its undercover officers to "avoid such easy detection by members of the public."

Now, about the claim from the "named employee"—the OPA doesn't identify officers against whom there are complaints—that I accidentally bumped into him? That's bullshit. I wouldn't bump into a police officer. I'd be liable to catch an assault charge if I did. I also wouldn't bump into someone who I was attempting to interview, or who I thought might become a subject of my reporting. I'd have to be an extremely sloppy and careless reporter to do so.

In a follow-up interview, Murphy told me he had no way to "break the tie" between my account and the officer's account of what happened. It was my word against the officer's. (It's not clear from Murphy's report what the second undercover officer might have told him about the incident, if anything. But I believe the second officer had already turned his back and started walking away when the elbowing occurred.) And the OPA's investigation didn't turn up any video from a nearby camera in the shopping center that could have authenticated my account.

"My statement that I found your account more plausible is reflective of my intuition about your account of the events," Murphy said. In his mind, though, his intuition doesn't constitute evidence that can tip the scales one way or another.

Michael O'Dell, another Black Lives Matter demonstrator, filed an OPA complaint about a man at another December demonstration who he suspected of being a police officer. When O'Dell attempted to take that man's photo, the man turned his back and then walked backward into him, O'Dell alleged in his own complaint. Once again, the man turned out to be a Seattle police officer, and the OPA found that even though both parties agreed that physical contact was made, "they cannot agree on whether it was the named employee or the complainant who walked into the other."

The OPA again issued a "Not Sustained (Inconclusive)" finding on whether the officer wrongly used force. Murphy said the officer in my case and O'Dell's weren't the same guy.

"I assumed this [complaint] would be unsustained," said O'Dell in a text message. "Of course he lied. He knows who made contact. Guarantee I'd have been arrested had I made the contact."

O'Dell was later arrested and accused of assaulting police officer Ronald Hylton during a protest on Martin Luther King Jr. Day. The charge was dropped, however, after a video surfaced on YouTube showing that Hylton tripped and fell during a fracas.

I'm not sure what else to say about this except that cops lie and our system allows them to get away with it. The one thing we've seen that can consistently hold them accountable is a clear video. Make sure you start filming as early as possible, preferably before the encounter itself even begins. In retrospect, I should have had my phone out and recording even before I asked the undercover cops who they were. Even if an officer is wearing a body camera, I would still advise you to pull out your phone and film what happens yourself.

This year, video clip after shocking video clip has provided "corroboration of what African Americans have been saying for years," Paul Butler, a professor at Georgetown University Law School and a former prosecutor, recently told the New York Times: There's a lot more bad police conduct out there than many have been led to believe.

As for Murphy, the OPA director: I'm glad he acknowledged my story to be more believable than the cop's. But if that's the case, why not penalize the officer in some way? It's true that SPOG's contract with the city specifies that dishonesty is grounds for termination, and the only way the department can find that an officer is dishonest is to provide "clear and compelling" evidence. Murphy's hunch that I'm not the one who's lying in this case doesn't rise to that evidentiary standard—if it did, it would represent just cause for terminating the officer's career. But until that section of the police union contract gets revised, couldn't he have found some other way to sanction the officer?

The larger question, however, is whether these guys who stick out like sore thumbs so much that they're regularly recognized by protesters—protesters who are already angry with and mistrustful of the police—ought to be there in the first place. Ron Smith, the president of SPOG, said they belong to "situational awareness teams" who are regularly deployed to protests. "The department sends them out there on all these things to monitor for property damage and violence," he said. He said they've been out at protests from Black Lives Matter to May Day, but he doubts they were deployed to protests against Shell Oil. "It depends on the intel that's there and who's expected to be there."

"If I was an anarchist," Smith said, "or even a regular protester, I would probably not want to be infiltrated by the police... Just like the dope dealer on Third and Pike doesn't want to get busted. That's the price of doing business. It's the whole package."

"As far as being professional in that role," Smith added, "they're in no obligation to do so, because they're trying to maintain that role."

In a statement, Patricia Sully, a staff attorney at the Public Defender Association, said use of these officers at protests "creates a sense of mistrust. Even if the intent of the officers or department is not to broadly surveil protests but rather engage in targeted crime prevention, the impact of such use of police resources at demonstrations can have a real and non-trivial chilling effect on First Amendment activity."

Sully called for more scrutiny of undercover officers, including whether they are engaging in "covert surveillance" of protesters, by the city's intelligence auditor, David Boerner—who's admitted he does not know how to audit electronic data. Officials say they're going to replace him and beef up the intelligence auditor role, but neither city council public safety chair Bruce Harrell nor Mayor Ed Murray have made it happen yet. recommended