Tongues are mostly spoken within the Church. Where there are tongues, there are also interpreters. Some tongues may indeed be false however, God has also given various believers the gift of discernment. This gift is able to define whether one is speaking in a tongue from the Lord or whether they are not. There is a prompting, an unction, a sense of alertness from the Holy Spirit that tells us when a tongue is not from God.Tongues aren't as clear because spotting fake tongues is totally subjective.
Any one who joins this forum, as an unknown and professes to be a prophet, will be heavily moderated. I would like to also point out that there are no "noted prophets" on this forum so your idea about "a true prophet" denouncing what was said would not come to pass.As to silencing a "prophet" I would offer two points: They should not be silenced unless they are doing something excessively provocative like if it's a profanity or something very threatening then of course they should be silenced (and removed). If it doesn't step to that level then they should be allowed to continue. At that point, if what was said was false, then it is for a true prophet to stand up then and denounce what was just said (with care) and then the service to move on. If the pastor feels the need to add an addendum or some point then he should. But I don't believe it's right to silence tongues or prophecies because I fear the Lord.
Btw: I do not believe that anyone here is trying to silence the gift of tongues or the gift of prophecy. There is a major difference between the gift of prophecy and the office of a prophet....If you call yourself a prophet then you are saying that you hold the office of a prophet. The forum leadership will not allow strangers to this forum who profess to be prophets to have a free reign with it's members....just a reminder. :)