While Nancy Pelosi, Harry Reid and Barack Obama would love to have laws on speech like the UK. Essentially if a prosecutor thinks you Twitter message is “menacing” you can be arrested.
Here’s a short excerpt from the AP:
Dorset Police said early Tuesday that a 17-year-old man was arrested at a guest house in Weymouth “on suspicion of malicious communications” in relation to Twitter threats made against Daley.
In Britain, tweeting messages considered menacing can lead to prosecution.