Garven, Wood, Malpass, & Shaw (1998) found that interviewing techniques from the McMartin Preschool case can induce preschool children to make false allegations of wrongdoing against a classroom visitor. In the present follow-up study, two specific components of the McMartin interviews, reinforcement and cowitness information, were examined more closely in interviews of 120 children, ages 5 to 7. Children who received reinforcement made 35% false allegations against a classroom visitor, compared to 12% of controls (p < .001). When questioned about "fantastic" events (e.g. being taken from school in a helicopter) children receiving reinforcement made 52% false allegations, compared to 5% for controls (p < .001). In a second interview, children repeated the allegations even when reinforcement had been discontinued. The findings indicate that reinforcement can swiftly induce children to make false and persistent allegations of wrongdoing.