Leaders who get to the top through their strong personalities risk turning their organisation into a personality cult, according to a leading business psychologist.

Howard Book of the Insead Business School was speaking at the International Conference on Emotional Intelligence. He said that despite their strengths, leaders with a high EQ (emotional intelligence quotient) could eventually stifle their employees if they are not checked by good infrastructure.

“If you come into a leadership position with a particular personality that means you are really adored, and you receive that constant message, it seems to melt your anchor. You start to believe the hype, to talk in terms of ‘it’s my organisation’ and act in ways that reflect that. Similar to a cult leader, you will increasingly feel the need to be idolised.”

Entitling his talk “The dark side of emotional intelligence” Book appeared on stage wearing a Darth Vader costume to illustrate his point about over-powerful leaders. He explained how emotionally intelligent qualities such as assertiveness and independence could boil over into unpleasant characteristics such as bullying and a lack of empathy.

“Groups in this situation become confused and anxious, and they regress, beginning to think about the leader in a highly distorted way,” he said. “Either they become very dependant on the leader, or they feel persecuted and see the leader as malevolent. You end up with two polarised views about exactly the same person and the same action.”

Strong infrastructure, such as clearly defined job roles and evaluations could stop such leaders having such a negative effect on group psychology, he added.