Groupthink occurs when people’s desire to maintain group loyalty becomes more important than making the best choices. People often find it hard to think and act independently in group situations. According to psychologist Irving Janis, groupthink is “a deterioration of mental efficiency, reality testing, and moral judgment that results from in-group pressures.”

Group members often suffer overconfidence and hold an unquestioned belief in the group’s competence and morality. Dissent by group members may be discouraged and even lead to expulsion from the group. Because people often want to avoid these punishments, they remain silent. This creates the illusion of agreement or unanimity in the group.

Groups may also reach decisions, including moral judgments, which are more extreme than any single member of the group originally supported. Unfortunately, if groupthink takes hold, group members may not even question ethically dubious decisions and actions. For example, some people say that the Bush administration’s decision to invade Iraq because of non-existent weapons of mass destruction was due to groupthink.

Indeed, groupthink can cause us to value harmony and consensus over independent judgment, and can lead to unethical behavior.