Shoppers walk past demonstrators blocking the entrance to a store on Chicago’s Michigan Avenue on Black Friday, days after the release of a video showing the 2014 fatal shooting of Laquan McDonald by a Chicago police officer. (Joshua Lott/Getty Images)

All year I’d been bracing for the police video that would come out of Chicago.

Then the footage of 17-year-old Laquan McDonald, who was hit with 16 bullets in 15 seconds, was released. And it wasn’t merely an officer-involved shooting. It looked like an execution.

When it comes to violence, Chicago never disappoints. Officer Jason Van Dyke has been charged with first-degree murder in the case. Protesters who disrupted Black Friday shopping in an upscale Chicago retail district are calling for the police superintendent, Garry McCarthy, to resign.

I didn’t know what the video details would be — that the teenager would be so obviously veering away from police, counter to police claims, or that we’d see smoke rising from the gunshot to his head. But I knew that the city Martin Luther King Jr. once called more “hostile” and “hate-filled” than Mississippi would have something special in store.

Here’s why.

I lived on the South Side of Chicago until I was 10. Last year, I returned to the city to do a story on gun violence — Chicago’s numbers are routinely among the worst in the nation — in my former neighborhood.

What I found were two sides of the same coin. In the neighborhood, there was ingrained suspicion of a police force that some people called “the biggest gang” in the city. At the police station, I faced suspicion as a black woman trying to engage with law enforcement.

In the neighborhood, I found a segregated, pressurized community with some residents so alienated and disaffected (terms we usually use when trying to understand white gunmen) that they were self-injuring with gang violence and guns.

The stories others told me were almost casual. Aaron Smith, a decorated 26-year-old veteran of the war in Afghanistan, said he was pulled over at the community center founded by his grandmother. An officer accused him of being a drug dealer. Called him a liar when he denied it. When Smith pointed to the Purple Heart decal on the bumper of his car, the officer accused him of buying the sticker on the Internet. The officer left, but never apologized.

When I walked into the local police station, it took me a few moments to process how I was being treated. Nothing dramatic, just a wall of white officers staring at me with ill-concealed hostility even as I tried to keep things light when I asked for information.

The contempt was so palpable that I saw fit to raise it in an interview with Robert Tracy, chief of the Chicago Police Department’s Office of Crime Control Strategies. Your station, I told the chief, is very anti-community.

“I’m educated. I know how to talk to people. I have resources,” I said. “How would a regular person just coming off the block” navigate that, I asked the chief.

Tracy wanted to know when I’d visited and whom I’d spoken to. But it wasn’t about an officer, I told him. It was a culture.

Michael Jenkins, an expert on community policing at the University of Scranton, calls the Chicago video scary to watch. All year, I’ve been talking to Jenkins, trying to make sense of video after video. He said that 2015 is a watershed year in terms of policing and accountability, and the McDonald death represents something more fundamental than just a bad shooting.

We have to start to pay attention to the ways police enter into these situations, Jenkins said.

“Essentially rolling up on the individual, then jumping out of the car and approaching him when they believe him to be armed and dangerous — when they do that, they are putting themselves in a situation in which they could reasonably believe their life is in danger,” Jenkins said. a

“They create these conditions in which every force becomes justified. We need to start holding police accountable for the actions they took that got them [into that situation] in the first place.” And for the mind-set with which they jump out of the car.

I mentioned to Jenkins the pervasive malevolence some people say they feel from police.

“I try to be more understanding of police and the stresses of their job,” Jenkins said, “but I think we need to be realistic about those attitudes and behaviors of our police and how they affect community relations.

“When you allow repeated racist jokes, when you allow officers to continue to disrespect and have contempt for the people they are policing,” he said, it all feeds into the backdrop of what we’re seeing across the country.

And winds up with what we saw in the video, the most stomach-turning yet.