John Darley

John Darley (b. April 3 1938) is a distinguished U.S. social psychologist, who has made contributions to the study of helping behaviour.

He studied at Swarthmore College from 1956-1960, where he obtained his Bachelor's degree (1960), and later attended Harvard University, from which he obtained his Master's degree in 1962 and his Ph.D.in 1965.

He is probably best known for his collaboration with Bibb Latane in looking at why people do not always intervene (i.e. offer aid) at the scene of an emergency, a research interest largely stemming from the tragic case of Kitty Genovese, the New Yorker who was murdered in a New York suburb in March 1964 in the presence of 38 witnesses, of whom not one did as much as telephone police services.

Experimental research with Bibb persuaded Darley that, other things being equal, more people present at the scene of an emergency could lead to reduced likelihood that any one would help, for two reasons:
 * Pluralistic ignorance, the assumption that because no one is helping, everything must be all right;
 * Diffusion of responsibility, a sense of shared responsibility when others are present.

Since 1980, further experiments by social psychologists have suggested important qualifications to this general rule, and identified conditions where increasing bystander numbers at the scene of an emergency may actually increase the likelihood of helping. One of Darley's most distinguished Ph.D. students has been Daniel Batson.