Observers are known to form inferences about an actor on the basis of the actor's behavior, regardless of the external forces contributing to that behavior. Two studies were conducted to determine whether this inferential error would also occur at the level of group activity. In the first study, 70 undergraduates read about a decision made by a nation, either the United States, Holland, or the Soviet Union, and then indicated the extent to which they believed that the nation's citizens held attitudes consistent with that decision. The results indicated that subjects made correspondent inferences between the nation's decision and the citizens' attitudes, particularly when the nation was an outgroup nation. In the second study, 60 undergraduates read a vignette about a jury decision which contained information on the final jury vote, the decision rule, and the final decision of guilt or innocence. The results indicated that subjects focused on the decision of guilt or innocence, and not just on the final jury vote, when attributing attitudes to jurors. These data suggest that people do commit the group attribution error, a tendency to assume a correspondence between a group decision and members' preferences, even when such an assumption may be unwarranted. The results from the first study further suggest that people are more likely to commit this error with regard to an outgroup than to an ingroup decision. (NRB)