> I'm not sure where the line is.

The line is always where a criminal violation seems likely to occur, including criminal negligence. Otherwise the government has no business butting in, unless subpoenaed as a witness by a court in a civil matter.

Edit: I guess the government also has a right to respond if it, or its policies, are a target of criticism or lies. But it should do this in the court of public opinion, or in an actual court if said speech breaches criminal law or a civil tort. Though in the latter cases it would be held to the highest standard. It has no right to otherwise shut down anyone's speech regardless of where it occurs.