The Nightmare That Scared Every New York City Parent 36 Years Ago Still Isn't Over

*UPDATE 5/18: Citing the lone holdout juror, Manhattan District Attorney Cy Vance on Monday announced plans to re-try the case.

On May 25, 1979, Etan Patz was allowed to walk to the bus stop in SoHo, Manhattan, by himself for the first time. Dressed in an Eastern Airlines captain's hat and armed with a dollar, he told his parents he wanted to buy a soda to eat with lunch.

Stan and Julie Patz never saw their six-year-old again.

The case stumped investigators and struck fear in the hearts of parents everywhere, but particularly in New York City. As Patz's face was plastered on milk cartons and projected in Times Square, people started discussing "stranger danger" with their kids for the first time. In 1983, Ronald Reagan declared May 25 "Missing Children's Day." Although a breakthrough in the decades-long mystery seemed to emerge in 2012 when 54-year-old New Jersey resident Pedro Hernandez confessed on tape, a judge declared a mistrial in the murder case against him Friday after a jury was deadlocked for a third time in as many weeks.

Until quite recently, the primary suspect in the case had been Jose Antonio Ramos, a convicted pedophile who lived in a Bronx drainpipe. He even reportedly told Assistant United States Attorney Stuart R. GraBois that he picked up a boy he was "90 percent sure" was Patz on the day he disappeared with plans to molest him, but ended up putting that kid on a subway when he resisted. Still, no one could wrangle a confession out of Ramos, and to to this day he denies harming Patz.

Three years ago, though, Hernandez—who was an 18-year-old convenience store clerk back in 1979—confessed to strangling Patz after several hours of police interrogation. The New York Times found that he first confessed previously in a Camden, New Jersey, prayer group and that his sister considered it an "open family secret." In fact, it was a tip from a family member that led to police picking Hernandez up for questioning.

Hernandez was indicted on November 14, 2012, even though there was no physical evidence linking him to the crime. His mental illness would also appear to meet the profile for a coerced confession as defined by the Innocence Project. He displays schizophrenic tendencies and has an IQ of around 70 according to his attorney.

"The really sad part of this case," Hernandez's attorney told ProPublica, "is that it will take time, it will take money and it will not tell the city what happened to Etan Patz."

The case has taken three years to prepare and conduct, but it seems likely we'll never know who actually killed Patz, though his disappearance has cast a long shadow. Although the idea of a kidnapper is obviously a universal concept, before May 25, 1979, it hadn't quite calcified in the national consciousness.

A young mother at the time of the kidnapping perhaps summed up the cultural shift when she spoke to a reporter for a 2009 feature on Katz. Back then the city was an unsupervised—but seemingly safe, at least by 1970s standards—playground for young kids who would skip home for dinner each night.

"It all changed after Etan," she told New York magazine. "We all looked at each other and said, 'Well, that world is gone.' "

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