Complex sentence: Bummer was still popular enough that, to avoid violence, the city immediately arrested Rippey, but he did not escape popular justice: on learning of his crime, his cellmate, David Popley, "popped him in the smeller".
Split into simpler sentences: Bummer was still popular enough that, to avoid violence, the city immediately arrested Rippey. He also did not escape popular justice: on learning of his crime, his cellmate, David Popley, "popped him in the smeller".