If you describe a decision, action, or idea as justified, you think it is reasonable and acceptable.
In my opinion, the decision was wholly justified.
在我看来,这个决定是完全合理的。
If you think that someone is justified in doing something, you think that their reasons for doing it are good and valid.
He's absolutely justified in resigning. He was treated shamefully.
他完全有理由辞职。他受了侮辱。