The topics mainly are drugs, murders and issue of cops and blacks. Some of those cops however have really serious issue of judgement to black people. Some of them said that they want justice for all, but in the end they just do things to cover their asses. Maybe that’s a real live in Chicago. The main characters in the story (member of intelligence) who have more experience than other cops are really emotional and sometimes they can’t control it. That’s the part that I don’t like from this series. How come they never learn from the experience, it’s a common sense to tell that they are good cops. And it has 7 seasons already. Please make those main characters a bit smart :(