in a la noire interrogation how do you get all the questions correct?

Answer 1

I go by process of elimination. The game saves right before you begin any questioning. So as long as you don't go outside the building your in, the game won't save. That way if you answer one wrong, you can just quit, then restart.

Also, if you have more than one person to interrogate, question both of them because sometimes one person will give you an extra question for the other person. Usually these are accusations.

I know it's not all the answers straight up, but it's the best I got. Hope it helps you!