Is it possible for a person to be trusted in kashruseven ifthe aveiros he does isn’t related to kashrus?
Not sure the Halacha about this but common sense would say that such a person can’t be trusted. Im sure it would depend which aveiros as well. Because if you mean Loshon Hora, that is something almost everyone struggles with on a regular basis. So Im sure it really depends which aveiros and if he does them befarhesya.