May be the result of failing to realize that an ethical dilemma exists, or it may arise from a variety of mental defense mechanisms.

Moral blindness may be the result of failing to realize that an ethical dilemma exists, or it may arise from a variety of mental defense mechanisms.
As the result of moral blindness, you just cannot see why something is bad, because you don't realize the implications that decision may bring. You are morally blind, meaning that good and bad are equal in your opinion.