Is There Really a Bystander Effect?

When Kitty Genovese was brutally attacked and killed on March 13, 1964, the news would shock the world.  Not because of the murder itself however, but due to reports that thirty-eight of her neighbours had watched the killing but did nothing.  According to the New York Times article describing what happened,  "Twice the sound of their voices and the sudden glow of their bedroom lights interrupted him and frightened him off. Each time he returned, sought her out and stabbed her again. Not one person telephoned the police during the assault; one witness called after the woman was dead."  

While later investigations would show that very few of the thirty-eight neighbours who had heard some part of the attack were really aware of what was going on (many thought it was just a lovers' quarrel), the idea that Kitty Genovese's murder was fully observed by numerous neighbours who "didn't want to get involved" quickly took on a life of its own.    Headlines about the callous, unfeeling New Yorkers who ignored Kitty Genovese's dying screams led to wide-scale soul-searching over declining social values and the dangers of urban life.  Television movies, books, and plays based on the Genovese murder would play up the unfeeling neighbour angle and spurred the passage of "bad samaritan" laws in some jurisdictions (with limited success). 

Kitty Genovese's murder also inspired psychologists Bibb Latane and John Darley to launch a series of classic experiments investigating bystander intervention in emergencies.  Using New York University students, they investigated factors that seemed to increase the likelihood of bystanders helping in different simulated emergencies.  These ranged from a simple theft to hearing cries of distress from an adjoining room.  In a finding that they would later term the bystander effect, Darley and Latane found that individuals were slower to respond as the number of others that the participants thought were present increased.  Participants who were alone in a room during the simulated emergency were far more likely to respond and response time was significantly slower in group ranging from two to six participants in size.

To read more, check out my new Psychology Today blog post.


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