@pluralistic Mention of "boss politics" & selective enforcement makes me think of “Big Tim" Sullivan, whose Sullivan Act made it a felony to carry unlicensed firearms in public in New York. The purpose was to disarm Sullivan's enemies; it wasn’t enforced against his friends.
Like many corrupt politicians, Sullivan also dispensed patronage. He reportedly used to say “I never asked a hungry man what his politics were. It was enough for me to know he was hungry.” That's not a Trump-like sentiment.