Today in History - December 16: Briefly successful escape undermined central claim of Alcatraz

When three men vanished from Alcatraz Federal Penitentiary in 1962, it was long assumed the trio had drowned trying to escape.

The argument from prison officials was that the water in San Francisco was too cold and too rough to survive in.

But another jailbreak on December 16 that year completely undermined that argument.

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John Paul Scott was found unconscious underneath the Golden Gate Bridge by a group of teenagers that morning.

He had managed to slip out of the prison, and wearing makeshift floaties made from rubber gloves, swam from the island to shore.

At some point during the swim he blacked out from hypothermia and exhaustion, but he survived.

Nevertheless, it proved that making it from Alcatraz to the mainland by water was possible.

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Scott's escape undermined claims from the prison officials that it was not possible to do so.

It further bolstered theories that Frank Morris and John and Clarence Anglin had successfully made it to land.

Despite their escape attempt taking place in summer, there is very little water temperature difference in San Francisco Bay between June and December.

Scott was the only known prisoner to successfully escape from Alcatraz, even if his freedom was incredibly short-lived.

Alcatraz would be closed three months later.

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While the escape attempts were cited as justifications for the closure, the truth was the prison was too expensive to run.

The cost to house someone there in 1959 was $10.10 a day compared with $3 at a federal prison in Atlanta.

It was cheaper to build a new prison from scratch.

Scott would spend the rest of his life in other federal prisons before dying behind bars in 1987.

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