Sure. Can you give me an example of something that's illegal to say in a group chat that coordinates legal observers?
I don’t know if anyone IS using such a database unlawfully - they might be checking the plate number against an Excel sheet they created based on other reports from people opposed to ICE - but if its a databse they shouldn’t be using in this way, if might be against the law.
But that's not an example of something that would be illegal to say in a chat. It would be an example of something that's illegal to do regardless of the chat.
Actual examples? No. I don’t believe it happened.
Hypothetical examples? Co-ordinating gunning down ICE agents. If the chat stays on topic to “coordinat[ing] legal observers,” there shouldn’t be liability. The risk with open chats is they can go off topic if unmoderated.