2) He’s a hero, but not a great guy
Unpopular opinion time: Hank Voight is a bad guy. He’s the hero of Chicago PD, and he does a lot of good on the show. But he also does a lot of bad things, and he’s really the lesser of two evils.
Remember when Voight was first introduced on Chicago Fire? He was menacing the crap out of Matthew Casey (Jesse Spencer) to protect his son. That scenario is classic Voight. His actions come from a place that’s good, but they are very bad. They’re immoral at best, many of them are illegal at worst. And that pattern of behavior hasn’t changed on Chicago PD. The only difference is we’re supposed to root for him because he’s the cop, and he’s taking down the drug dealers and gang bangers and other worse people in Chicago.
But as many fans have pointed out, that doesn’t necessarily make what he’s doing okay. He’s done a lot of things that make TV viewers arch an eyebrow. Remember how he maimed a woman in last season’s “Remember The Devil” when she wouldn’t talk? It’s up to you if you give him a pass for the behavior based on the motivation, but let’s be honest and admit he’s the villain in any other story.
Voight is the only One Chicago protagonist to have already spent time behind bars, so having him go there in Chicago PD season 5 would just be part two. And it would be appropriate, all things considered, because at what point does he have to face justice?