Most importantly, you are telling the world that anyone saying the same thing is in a risk of losing their tongue, regardless of correctness of the information.
That makes it cheaper for people to argue against the information than to argue for it.
And that increases that chance that people will finally consider him a liar.
The effectiveness of silencing someone really depends on how common such silencing is for a given regime. For example, if a regime silences all critics (regardless of whether they tell the truth or lie) an individual act of censorship doesn't carry any information about whether the censored info was true or false.
On the other hand, tons of claims are made against the US government every day, and no action is taken against almost all of them. If the government suddenly acted to silence one conspiracy theorist, far more attention would be paid to his claims, and the action would likely backfire.
Another month has passed and here is a new rationality quotes thread. The usual rules are: