It's something most grass roots activists don't feel intuitively at all.

They look for spies among their own level but it's almost always going to be the organisers, the helpers, the ones with the van, the one that can print your posters, the one with a bit of spare cash, the dude who can set up your server and the friendly friend with time to help you personally that are the spies.

Logically it makes sense for a spy to be placed as high as possible to get more information, and yet activists look for spies among the rank and file. They look for odd people to label as the spy. They expel the outsider. They suspect the ones that don't fit in. But the spy is going to be a well adjusted normal insider that they already trust, almost always!

I find it so interesting. It happens again and again. It's probably the same pattern for any group that attracts any government attention.