You can use many adjectives and nouns to describe someone who can't tell right from wrong. But, in your specific context, I would suggest using "indoctrinated". To indoctrinate means:
Teach (a person or group) to accept a set of beliefs uncritically
the process of forcibly inculcating ideas, attitudes, cognitive
strategies or a professional methodology (see doctrine) by coercion.
As Jim suggested in the comment, "brain-washed" is a synonym of indoctrinated. To brainwash means:
Pressurize (someone) into adopting radically different beliefs by
using systematic and often forcible means
[Oxford Online Dictionary, Wikipedia]