Why do crimes by some members of a group invalidate the group ?
Boy Scout leaders were **** do - did we call to disband the Boy Scouts organization ?
What invalidates the group is when they cover up for crimes committed by members. There will be
**** in all groups, it's what the group does about it that invalidates or clears their name.
For religious groups there is an added element of hypocrisy/evil because when you claim to be chosen specifically by God - there's more of an expectation of good behaviour. Or at least better than average, otherwise why bother with a religion.