ABC’s Primetime has staged a series of experiments in recent years under the rubric “What Would You Do?” which enact provocative scenarios while hidden cameras capture the reactions of the public. Chris Whipple, the producer who conceived the series, refers to it as a “Candid Camera of ethics.” Starting with a nanny verbally abusing a child, the series has gone on to present similar scenarios: an eldercare attendant ruthlessly mocking an old man; a group of adolescents bullying a chubby kid; a man viciously berating his girlfriend, seeming on the verge of violence; etc.

The sequences tend to begin with the narrator pointing out that many pass right by the incident. Several witnesses are confronted and asked to explain why they didn’t step in. One man, who gave the fighting couple a long look before continuing on his way, reveals that he is an off-duty cop and says he determined that no laws were being broken, so there was nothing for him to do. The focus shifts to those who did intervene, and the camera lingers over the confrontations, playing up the drama.

These experiments are, in a sense, the flip side of the reality-TV coin: rather than show how people act in manufactured situations when they know they’re being watched, they show us how people act when they don’t. And the experiments have clearly appealed to viewers. From the first minutes of its first hour, when its ratings doubled those of the previous week, “What Would You Do?” has been a success. After appearing periodically in 2005 and 2006, ABC ordered five new hours that were scheduled to air last November before the writers’ strike put them on hold. It is, Whipple says, highly “watchable” television.

In the world of print, Reader’s Digest has come closest to making such experiments a franchise. Over the last two years, the magazine has pitted cities around the world against each other in tests of helpfulness and courtesy, to determine which city is most hospitable. The first round used the following three gauges to separate the rude from the solicitous in thirty-five cities: the percentage of people who picked up papers dropped by an experimenter; the percentage who held the door for experimenters when entering buildings; and the percentage of clerks who said “Thank you” after a sale. When the scores were tallied, it was clear that Reader’s Digest had hit the counterintuition jackpot: the winner was New York City. According to Simon Hemelryk, an editor with the UK edition of Reader’s Digest who came up with the idea for the tests, the press response was “totally, totally mad.” Hundreds of media outlets picked up the story. David Letterman presented a tongue-in-cheek, top-ten list of the “Signs New York City Is Becoming More Polite.”

The notion that New Yorkers are more polite than commonly believed was also at the center of a 2004 experiment conducted by The New York Times. Reenacting an experiment originally performed by graduate students of social psychologist Stanley Milgram at the City University of New York in the early seventies, two Times reporters asked riders on crowded subway cars to relinquish their seats. Remarkably, thirteen of fifteen did so. But the reporters found that crossing the unspoken social boundaries of the subway came at a cost: once seated, they grew tense, unable to make eye contact with their fellow passengers. Jennifer Medina, one of the reporters, says that she and Anthony Ramirez, her partner on the story, found the assignment ludicrous at first. “It was like, ‘What? Really? You want me to do what?’” she says. “We made so much fun of it while we were doing it, but we got so much feedback. It was one of those stories that people really talked about.” And papers around the world took notice: within weeks, reporters in London, Glasgow, Dublin, and Melbourne had repeated the experiment.

In these journalistic experiments, the prank always lurks just beneath the surface and is clearly part of the genre’s appeal. During ABC Primetime’s experiments, there always comes the moment when host John Quiñones enters and, with a soothing voice and congenial smile, ends the ruse. These people are actors. You have been part of an experiment. And in that moment, no matter how serious the scenario, there is always the hint of a practical joke revealed, a touch of “Smile, you’re on Candid Camera!”

Daniel Weiss is a freelance writer based in New York City.