Halo/horn effect is a form of interviewer bias, occurring when the interviewer rates or judges an individual based on the individual’s positive or strongest traits, allowing their overall perception of the person to overshadow any negative traits. Referred to as the “halo effect” when it works in the candidate’s favor or the “horn effect” when it works against the candidate.
In social psychology, horn effect is the tendency to make a generalization in judging a person from one negative characteristic to a total impression. (The 'horn' is associated with the Devil). A negative form of halo effect.