People have to understand that a bad "one of us", is
not better than a good "one of them".
Mother Teresa did some good deeds,
but she was a Roman Catholic.
Mahatma Gandhi did some good deeds,
but he was an Indian.
Joesph Stalin did some bad things,
but he was a Soviet.
But? But! What the hell difference does it make? It's what they did, how they acted, what they accomplished, that defines them.
If you see/hear someone doing what you feel is wrong, say so. Doesn't matter if it's "one of us" or "one of them", speak out. That goes double for someone doing wrong, while claiming to represent you. Don't let anyone use you or your name, for evil, just because they are "one of us".