JAS 4:11

11 Do not speak lashon hora against an Ach b'Moshiach. The one speaking against an Ach b'Moshiach or setting himself up as a shofet [(judge)] of his Ach b'Moshiach speaks against the Torah and sets himself up as shofet of the Torah. Now if the Torah you judge, you are not Shomrei HaTorah but a shofet.