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Diffusion of Responsibility

Darley and Latané (1968) hypothesized that bystander apathy was caused by a dilution of the individual's sense of responsibility in a larger group of people. This diffusion of responsibility theory was tested in a laboratory experiment. Subjects thought they were overhearing another student have an epileptic seizure. In some conditions, the students were told they were one of two subjects. In other conditions, they were told they were one of six subjects in the experiment. In the six-person condition, 31% of the subjects responded to calls for help. In the two-person condition, 85% of the subjects responded.

What experiments supported the diffusion of responsibility theory?

Similarly, Latané and Rodin (1969) staged an experiment at Columbia University. They had students meet an experimenter, then divide up to fill out a questionnaire. Each student was assigned to a cubicle. Suddenly there was a crash and scream from one of the cubicles and a girl student's voice called out, "Oh My God, my foot! I can't move it! ankle...I can't get this thing off me!" Of course, the "accident" was faked, but the subjects presumably thought it was real. When subjects were by themselves in a cubicle, 70% responded. When subjects were grouped in pairs, only 40% responded. These findings were consistent with the Darley and Latané hypothesis. Together, the experiments showed that the same effect occurred whether people thought they were in a larger group or actually were in a larger group.

Both of these studies were artificial. Subjects may have been suspicious that the emergency was faked. To test the diffusion of responsibility theory in a naturalistic (real-life) setting, Latané and Darley (1970) set up a fake robbery in a liquor store. The robbers were two young men who entered the store and asked the clerk about an expensive imported beer. The clerk (who, like the two men, was a confederate of the experimenter) said he would have to check in the back room. He left the front of the store. The two men then grabbed a case of beer, saying, "They won't miss this," and went out the door.

The point of the experiment was to see if other customers (who thought the robbery was genuine) would mention it to the clerk, when the clerk came back to the front of the store. When customers were alone, 65% reported it. When customers were in a group of two, 56% reported it. This effect was quite a bit smaller than the diffusion of responsibility effect in the laboratory studies, although it was in the predicted direction. (Latané and Darley, 1970)

What personal characteristics of the victim were found to influence bystander apathy?

Personal characteristics of the victim were found to influence bystander apathy. Piliavin, Rodin, and Piliavin (1969) conducted a study in naturalistic conditions. They arranged for a confederate of the experimenter to collapse in a New York subway. In one version of the experiment, the man was dressed like a bum, sported a three-day growth of beard, and smelled strongly of alcohol. Most people failed to help him as he collapsed into a heap on the floor of the subway car. When a well-dressed businessman type was used in the same experiment, more passengers responded with offers of help.

Other studies showed that previous personal contact encouraged helping behavior. A brief period of conversation with a "victim" made subjects more likely to respond during a pretended emergency.

ories that explained the effect of personal contact?

Two theories were developed to explain the effect of personal contact. One possibility is that people "identify" with a person more after social contact and are therefore more likely to help because we empathize with the person. Another possibility is that people who are in face-to-face contact with a person do not wish to view the consequences of a failure to act. Not wishing to see an unpleasant scene, people offer help. (Piliavin, Rodin, and Piliavin, 1969)

A combination of these two variables-being-to-face with a potential victim and not wanting to see unpleasant consequences-provides the most powerful motivation for people to help out rather than be "apathetic." Williamson, Swingle, and Sargent (1982) report a case involving both elements. It began when a 23-year-old woman started to give birth on a commuter train in Chicago.

How did commuters respond when a woman started giving birth?

Commuters acted as midwives, bystanders applauded and yelled, "Praise the Lord!" and a shopper offered a newly purchased baby blanket to cover the infant. When the paramedics arrived, according to the Chicago Tribune for June 1, 1981, one remarked that "Everybody was working in unity, and there was a lot of harmony, and it was beautiful. People clapped afterwards, and what struck me was how people can work together in a unity when they have to." (p.391)

What factor made seminary students ignore a man slumped in a doorway?

Other factors could also influence bystander apathy. Darley and Batson (1973) asked seminary students (students studying to become preachers or ministers) to rehearse a speech in one room, then go to another room to deliver the speech to a waiting group. On the way to the second room, each student passed a person slumped in a doorway. If the experimenters made the students think they were late for their speech, only 10% helped the stranger. If they students thought they were early for the speech and had time to spare, nearly half of them helped out.

What was Kelman's warning, and how did it come true, 20 years later?

Eventually, the frequent occurrence of experiments involving fake emergencies led to greater suspicion among subjects. Students read about experiments in social psychology in their introductory psychology classes and, when it was time for them to serve as subjects in a psychological experiment, they were "wise" to the deception. Kelman (1967) warned that social psychology experiments involving deception could backfire if subjects became suspicious every time they entered a psychological laboratory.

MacCoun and Kerr (1987) said that Kelman's prediction came true at their school. A subject had a real seizure during an experiment. Several other subjects were present, but only one (a lifeguard) quickly helped. The others were suspicious that this seizure was being faked for the experiment.

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