Tsukauchi is a detective, he happens to be one who is by the books when it comes to law. This means he considers vigilantes (they do help where pro-heroes can’t) villains, because it is illegal to use your quirk without a license due to restrictions and laws. (This part ISNT canon but please roll with it, he is a lie detector and he audibly makes a different noise depending on if it’s a lie or not, that’s his quirk. Work with it).