Bearbrook (start of family DNA), Dirty John, Man in the Window (Golden State killer) , Murder book, Running from Cops (about the making of the show Cops) all US true crime. "Root of Evil" crazy show about a crazy family possibly linked to Black Dahlia case.
"The Dark North" is great show about mafia in Montreal - someone mentioned "Crimetown" it's a bit similar to that, but with insane French Canadian bikers.
BBC show 'Shreds' really good on police corruption, false convictions etc set in Wales. Really good.