Of course, the person who is trustworthy while in the ambit of the community and its norms and sanctions might be completely untrustworthy outside that community—where its norms do not reach. It is especially problematic for trustworthiness as moral or other commitment if these are group specific. Ethnic and even merely neighborhood conflict is commonly exacerbated by the attitude of a group’s members that nonmembers are proper subjects for exploitation and abuse. Indeed, they sometimes think it actively a good thing to abuse certain outsiders.

XREF: Connects to moral relativism and in-group/out-group psychology literature, plus the 'bad apple' vs 'bad barrel' debate about situational ethics.

Russell Hardin, Trust and Trustworthiness, loc. 827