This remark appears in the form of a question to add emphasis. This can be translated as a statement. Alternate translation: "Our Jewish law does not allow us to judge a man ... what he does!" (See: [[rc://en/ta/man/translate/figs-rquestion]])
Here Nicodemus speaks of the law as if it were a person. If this is not natural in your language, you may translate it with a personal subject. Alternate translation: "Do we judge a man ... does?" or "We do not judge a man ... does." (See: [[rc://en/ta/man/translate/figs-personification]])