+One strength is that other studies have demonstrated the influence of situational variables on obedience. In NYC, Behman conducted a field experiment and had 3 confederates dress in different attire: a jacket and tie, milkmans outfit and a security guard's uniform. The confederates individually stood in the street and asked strangers to do various tasks; pick up litter, give them a coin for the parking meter. People were twice as likely to obey the security guard than the jacket and tie this supports the view that situational variables have a powerful effect on obedience.