Actually the rationale would not be a preference for government, but some active hatred, vendetta, or resentment against the family member
I think that's generally right, but sometimes the state gets pretty good at indoctrination. Right now the schools are actively campaigning to get children to be vigilant about drugs, spousal abuse, terrorism, and the like. Children are being asked to put state security over filial piety.
Ever seen the movie Rotation? It is the story of a German family that becomes divided over supporting the Nazis. The father considers joining the Nazi party in order to improve his financial situation, but after witnessing some brutality he helps print resistance leaflets. His son, a Hitler Youth member, betrays him to the police. It's a pretty good telling, from a German point of view, about life in Nazi Germany, and it ends on a conciliatory note. After the war father and son meet again, and the guilt-ridden son is accepted by his father.
Our family isn't so dysfunctional that it would come to betrayal for something so trivial. I hope. Personally, I think I'd try to shield a family member from prosecution no matter how heinous the alleged crime.