Will Eyewitnesses to a Crime Take Action?

Feb. 21, 2008— -- It was a typical afternoon at the Reservoir Tavern, a family restaurant in a quiet suburban New Jersey town. The customers enjoying their lunch were completely unaware that someone in the restaurant was about to commit a crime. ABC News had arranged for actors to stage a theft at the restaurant to see how witnesses would react when a woman steals a man's wallet.

A blond middle-aged woman walked into the bar area and cased the place, pacing from one end of the bar to the other. Her eyes were drawn to a customer who had left his wallet out on the bar. She quietly plucked the wallet off the bar and slid it into her coat pocket. She passed many other patrons as she walked out the door and down the stairs.

At first, no one said anything or made a move. A man at the end of the bar clearly noticed what had happened, yet he did nothing … at first.

Ten seconds passed, and the eyewitness continued to relax at the bar. Not until the victim shouted, "Did somebody just take my wallet? Holy s***! Did you see my wallet?" did anyone make a move.

The eyewitness then jumped into action and ran out of the restaurant after the thief.

Watch the premiere of "Primetime: What Would You Do?" Tuesday, Feb. 26 at 10 p.m. ET

Yale psychology professor Jack Dovidio said people who witness crimes don't always react right away. Even though the customer saw the wallet getting stolen, he may have been "confused."

"The wallet's there, someone takes it, [but] nobody else says anything," Dovidio explained. "Once the situation was clear to him, he knew what he had to do."

The eyewitness, Deszo Benyo, caught up with the thief in the parking lot and brought her back into the restaurant. When asked why he got involved, Benyo said he "just stopped something that happened that shouldn't have happened." Benyo said he would have stepped in regardless of the sex or age of the thief.

Benyo's friend, Avon Prior, was sitting next to him at the bar. Prior said he was proud of his friend and credited adrenaline. "I'd want somebody to help me if I was in that situation," he said.