The characters of tragedy are in some sense responsible for their errors. However, given their ignorance of the consequences of their actions, it seems that they ought not be held responsible by others for what they have done. This is a paradox. The way to resolve the paradox is to distinguish two kinds of agent responsibility: accountability and culpability. Being accountable is primarily a private affair, whereas being culpable entails the possibility of just punishment.
"Tragic Error and Agent Responsibility,"
Philosophic Exchange: Vol. 35
, Article 4.
Available at: http://digitalcommons.brockport.edu/phil_ex/vol35/iss1/4