The car that came closest to running me over at a protest was silver. I don’t remember the make or model, just the color, and that it was big, a truck or SUV. I had to look up when speaking to the driver as I told him not to drive through the crowd of people.

It was 2015, and the thousands of people at the Boston protest against police had overflowed into public streets, surrounding several vehicles, including the silver one. This happens all the time at protests — while I’ve seen countless drivers raise their fists in solidarity with protesters, or take photos and videos from their cars, or dance and sing and chant with us, I’ve also seen angry bystanders, furiously honking their horns and fuming and swearing and even getting out of their cars to threaten protesters. But this guy sticks out in my memory. I remember feeling the weight leave my body, like I was bracing for a punch.

He had his window down and was screaming. I was trapped in front of his car, and the crowd spread in every direction around us. As is often the case when protesters urge drivers not to gun it through a crowd, it was not that I wanted to get revenge on him in some way by preventing him from getting where he was going; it was that there was no way to clear a path for him. A protest is not a military formation: there is no commanding officer to coordinate the movements of the crowd. There is power in that, the sense that one is giving oneself up to the collective, but it is also a logistical complication — I’m sorry, you can’t drive through this crowd.