Border Patrol shoots woman on Southwest Side; agents, protesters battle for hours
chicago.suntimes.com
The shooting occurred Saturday in Brighton Park when federal patrols were "rammed by 10 cars," according to a statement from the Department of Homeland Security, which has yet to be verified. In the protests that followed, agents used tear gas and pepper balls.

In other words, she was doing the kind of thing they do to random people all day long. Knowing how cops feel, it was probably an ordinary traffic jam.