FERGUSON, Mo. — In August, protesters shouted “Hands up, don’t shoot!” and “No justice, no peace, no racist police!” Now, three months after Michael Brown was killed by Darren Wilson—and days or hours before the grand jury’s decision—the demands have become a base ultimatum.

“What do we want?”

“Darren Wilson!”

“How do we want him?”

“Dead!”

Protesters formed a mob Thursday night in front of the Ferguson Police Department, fenced off in expectation of mayhem following grand jury. As cars approached a group of about 20 men and women, a cry went out: “Honk your horn!” If the driver complied, they were allowed to pass. If not, they were harassed.

“Who shut shit down? We shut shit down!” protesters boasted as they blocked one lane of traffic before police emerged from the building. Some later claimed that a cop shook a can of mace, an uncalled for act of aggravation, one man said. This alleged offense prompted the protesters to move out of the street and up to metal barricades preventing entrance to the police station’s parking lot.

On the other side was the line of cops representing the St. Louis County Police Department, the Missouri State Highway Patrol, and other agencies from the glut of surrounding municipalities. They took it in stride, but protesters reserved a special type of vitrol for the black cops on the line.

“You out here ‘cause you think you doing the right thing!” one man screamed.

“But you ain’t doing the right thing! You out here supporting a killer!

“They takin’ your sons!”

One African American officer smirked, possibly an attempt to laugh off the disturbing comments being launched in his direction. It was an unsettling and uncomfortable environment, one that is sure to have right-wing Darren Wilson supporters saying “I told you so” about protesters who are sometimes seen as nothing more than advantageous troublemakers.

For the left, whose far side was represented last night by at least one member of the Revolutionary Communist Party, the situation might be one worth dismissing as the mad rants of a few unruly members of the community.

Although one black photojournalist, a young man from the area who has been covering events here since the day Wilson shot and killed Michael Brown, was at a loss.

“I just don’t get it,” he said, shaking his head. “I don’t understand what the point of this is.”

It may be nothing other than anger and despair, at this point. With widespread speculation that Wilson won’t be charged, that could be a toxic combination, and one that might turn into the worst case scenario many are expecting: riots, looting, violence.

For months protesters have called the police the aggressors. And at points in August, they were absolutely right. I watched as cops shot tear gas toward a group who was helping an injured woman to her feet—they fashioned a splint to keep her ankle straight despite being fired upon. Police took people to the ground sometimes with impunity, wrenching arms behind backs and slapping cuffs on anyone who didn’t move quick enough. They did the same last night, after telling the protesters they would be arrested if they kept blocking traffic. Three were scooped up, including a 25-year-old man who is accused of pushing cops before being pepper-sprayed and taken away. “I ain’t afraid of cops,” he said, according to The Guardian.

That’s what many are afraid of. That no one will respect the grand jury’s decision—a mechanism of the law that, however wrong, unjust or unfair it’s perceived to be will likely mark the final legal event of note in the case of Darren Wilson. So, while the smirk that swept across the black cop’s face Thursday night might have been a slight betrayal of his attempt at stoicism, to the protesters who taunted him it was tantamount to a capital offense.

“You think this is funny?” they screamed. “You think racism is funny?”

He didn’t answer, obviously.