Who Takes Responsibility?

 In a situation where something bad were to occur and I was involved, while knowing others were involved, I think responsibility should be taken by all. For example, if I helped someone else take something from someone, I believe I should take some responsibility. I believe this because I do not believe it would be fair to claim that I am the sole person responsible behind the situation, while knowing that someone else was involved. Even if it means that that person may no longer be friends with me, I still feel it is only fair if both of us were to take responsibility for the action that has been committed, if it involves both of us. How I determine if I should take responsibility is that if I am involved in the action and caused some kind of contribution towards making the action occur, then I will take some responsibility. In a situation where, I see the action happening and I am not involved, I do not believe that I should take the responsibility, unless I know I could have done something to stop it. This is how I am able to know if I should claim responsibility or not.