Voight had to lecture Upton as her supervisor. It might have been over acted a bit but she definitely deserved it. And he put her notice when he questioned Rojas. They telegraphed what they were going to do last week when she picked the lock during the raid and Ruzek commented they'd have to talk about that .
I get the impression he can live with being a dirty cop but he'd rather implement personal vigilante justice because it's just a matter of getting a way with that act. But if he's questioned about his or team's actions he's put in a position to purger himself along with the crime. Upton's and other's actions take things out of his control, he's very measured in what he does. Now Voight might have to take a risk he never even planned for let alone wanted to do.
And yes he doesn't want the team to act like he does, in a way legitimate cases/arrests help him redeem himself, it's not just about keeping his job or staying out of jail.