IN ONE STUDY, 240 SUBJECTS READ SCENARIOS OF AN EVENT WITH A NEGATIVE OUTCOME INVOLVING ONE, TWO, THREE, OR FOUR INDIVIDUALS. AS PREDICTED, THERE WAS A SIGNIFICANT INVERSE RELATIONSHIP BETWEEN THE NUMBER OF PARTICIPANTS AND THE DEGREE OF ATTRIBUTED RESPONSIBILITY. THE SECOND STUDY INVESTIGATED SUBJECTS' ATTRIBUTIONS OF RESPONSIBILITY FOR CRIMINALS COMMITTING A CRIME ALONE OR WITH A PARTNER, ALTHOUGH THERE WAS NO DIFFERENCE IN SENTENCE LENGTH ASSIGNED. IN THE THIRD ARCHIVAL-TYPE STUDY, PRISON SENTENCES FOR CRIMINALS WHO HAD ACTUALLY COMMITTED A ROBBERY ALONE OR WITH OTHERS WERE EXAMINED. AGAIN, THERE WAS DIFFUSION OF RESPONSIBILITY: CRIMINALS ACTING ALONE RECEIVED SIGNIFICANTLY LONGER SENTENCES THAN PERPETRATORS WHO HAD COMMITTED A SIMILAR CRIME, BUT WHO HAD ACTED WITH OTHERS. IN ALL THREE STUDIES, THE RESULTS INDICATED THE PHENOMENON OF A GROUP'S DIFFUSION OF RESPONSIBILITY; AN INDIVIDUAL IN A GROUP SHARES IN THE RESPONSIBILITY FOR THE OUTCOMES THAT THE GROUP OBTAINS, WHILE PERSONS ACTING ALONE ARE VIEWED AS HAVING A RELATIVELY GREATER DEGREE OF CULPABILITY FOR THE EVENTUAL OUTCOMES OF THEIR ACTIONS. A LIST OF REFERENCES IS GIVEN. (AUTHOR ABSTRACT MODIFIED--MJW)