got all clues and questions in golden butterfly but only got 3stars?

Answer 1

You might have charged the wrong person. If you charge Moller, you can't get more than 3 stars. If you charged Eli and only got three stars, it might be because you got too many penalties. Follow this guide for more info: http://www.sleeandtopher.com/guide/l-a-noire-the-golden-butterfly-case-guide/