Okay, so there were some police officers who were pretending to be someone they weren't. They were pretending to be a part of groups of people who were trying to do things that the government didn't want them to do, like protesting or trying to make big changes.
The cops were doing this secretly, without telling anyone that they were actually working for the police. They were listening in on conversations, going to meetings, and sometimes even dating people in these groups, all while pretending to be just like everybody else who wanted to make a big difference.
But some people found out about these spy cops, and they were really angry. They felt like the police had lied to them and tricked them, and that the cops were using their power to spy on people who were doing nothing wrong.
Now, the government is trying to figure out what to do about it because some people think that what the spy cops did was really wrong, and other people think that it was important for the police to keep an eye on these groups.