Is it a baby-boomer thing? I always thought it was Sovereign Immunity combined with the police acting as agents of the state.

Sovereign Immunity always seemed overall a good idea to me, but its negatives should be mitigated by making the government as small as possible in the first place.

It doesn't seem like there'd be a need for a "right to petition the government" if you removed Sovereign Immunity, since you could otherwise go through the courts. So I don't think it's recent.