To have morality, it is defined by having one’s actions already predetermined to cause it.
For example, a man has been attracted to his another woman and he decides that the only way to do so, he must kill his wife and 4 children. He knows that it is impossible to escape the house in the event of a fire. Before he leaves on a business trip, he sets up a device in his basement that burns down the house and kills his family.
Was he fully morally responsible for killing his wife and children? How about this. Suppose one was kidnaped and forced to commit a series of terrible murders. The kidnaper makes them shoot the first victim by forcing them to pull the trigger, then mesmerize them into poisoning the second victim. Later throws them from an airplane, causing them to squash the third victim. Unbelievably, they survive the fall from the airplane. As they leave the scene they are approached by the police, who handcuff them and charged them with murder. The parents of the victims are extremely in pain by what happened.
Are the police and parents fair to blame them for the killings? One might say, obviously not, for they did not have an excuse because they did not act of their own free will. They could not help what they did; they could not have done otherwise. Only those who act freely are morally responsible.
Everybody believes that one may have free will. How could one not? Rejecting the idea of freedom would mean, one would no longer be planning for the future because why make plans if they are not free to change what will happen? Therefore, it would mean rejecting morality, for only those who act freely deserve blame and punishment? Without freedom, one may go along with predetermined paths, unable to control their destinies. That life is not worth living. One may question; how can one be responsible for the consequences of such free choices, that were determined outside themselves, beginning long ago?