How should someone who committed a crime for some good cause be punished?

Judging the rightness about someone’s action might be really hard, especially doing something with goodness, but crime related. I do not know about criminal law or these system, but they would operate to consider human rights and social regulations. Therefore, if dependents were admitted to get a reason matched with these considerations, they would set free from their commitment or reduce their sentences. However, these legal process, to deduce causes from the result, is not always clear and judges should doubt dependents could modify the situation and evidences to cover the truth. As a result, the dilemma, between to keep justice and not to make person who acts goodwill, but leads unfortunate outcome, always exist. So I think we might try to develop our legal system get trust, and follow their decisions rather than to argue with a case on grey area.