Reply To: Questions on Yoreh Deah, Choshen Mishpat

Ok. If we had proper witnesses that he certified non-kosher food as treif, I think that would be similar to the shochet or butcher who sells trief meat as kosher.

The halacha of the shochet is that even after one time he is pasul leidus and also not trusted to sell meat. To so teshuva, he must wear black, go to a different city where they do not know him, and show us his resolve by saying and animal is treif even at significant loss, or returning a found object at significant loss. (CM 34)

Additionally, the mechaber says in YD 1:14, that if even ONE witness says that a shochet is selling treif, although in most cases this witness is not believed, we would need to weigh the reputation of the witness and shochet and in some cases we would pasul the shochet.