Bernard Coy, the convict who planned the escape, had been convicted of a bank robbery in 1937 and was sentenced to 25 years. After being moved to Alcatraz in 1938, he became the cell house orderly, and thus, was relatively free to move around the main cell block. One of his main accomplices, Joe Cretzer, was a West Coast gangster sentenced to 25 years for murder. Cretzer had already attempted to escape in the past and faced another murder charge. As so, he was moved to Alcatraz. He and Sam Shockley along with two other convicts tried to escape earlier. Clarence Carnes was the youngest inmate at Alcatraz. He was convicted of murder in 1943 at the age of 16. After other escape attempts, he had a life sentence and 99 years for kidnapping. He was transferred to Alcatraz in 1946 after several other escape attempts. The third convict involved in the main plan was Marvin Hubbard. After the attempt began, these three were joined by Miran Thompson and Sam Shockley.

Coy Had The Freedom To Figure It Out

Because of Coy’s freedom, he was able to note flaws in the security of Alcatraz, and he saw that the gun gallery had minimal protection as it was only behind bars. Those bars could be spread apart using a device that consisted of a nut and bolt with a client metal sleeve. When the nut was turned with a small wrench, the metal sleeve moved. Additionally, because of the set routines, the convicts knew when the main cellblock and gallery would be left unobserved.

On the day that the battle began, May 2, 1946, most of the convicts and corrections officers were outside of the main cell house. Coy was sweeping the floor around C Block when Marvin Hubbard, who had been cleaning the kitchen, called officer William Miller to let him in. Miller started frisking Hubbard to ensure he hadn’t stolen anything, and as he was engaged, Coy attacked from behind. Once Miller was overpowered, the two were able to release Cretzer and Carnes from their cells.

Since Coy attacked Miller while Burch, the officer who patrolled the gun gallery was away, Coy, who had been starving himself, was able to widen the bars and squeeze between them. He then overpowered Burch when he returned, and passed some weapons along to his accomplices, keeping a Springfield rifle.

They Were Foiled By A Jammed Lock 

The convicts entered D Block, where prisoners were kept in isolation. There, they forced Cecil Corwin to open the door to the main cell house and released around a dozen prisoners, including Sam Shockley and Miran Thompson, who joined Coy, Carnes, Hubbard, and Cretzer in the main cell house, while the others returned to their cells. They then locked Miller and Corwin in a cell in C Block.

From here, they planned to get the key to the yard door, and then head down to the dock and hijack the prison’s launch, which docked on a regular daily schedule. They were going to use the hostage officers as cover as they made their way to freedom. However, although they did find the key, the lock was jammed, and so they were trapped in the cellblock.

With their escape attempt foiled, they seized officers who had entered the cellblock either as part of their routine or they were perhaps investigating the missing officers. The convicts ended up holding nine officers in two cells. The convicts then decided to shoot it out and began firing at the officers in the watchtowers.

Their Last Stand Failed

As they realized their plan had failed, Shockley and Thompson convinced Cretzer to shoot the hostages so they couldn’t testify. Cretzer did so, wounding five, with Bill Miller dying from his wounds later. While Carnes, Shockley, and Thompson returned to their cells, Coy, Hubbard, and Cretzer decided they wouldn’t surrender.

When Warden James A. Johnston requested help from troops at nearby Naval Station Treasure Island, two platoons were sent to Alcatraz to guard the general population of convicts and retake the cell house from the outside. That evening, unarmed officers entered the cell house, covered by armed officers in the gun galleries. They locked the door to D block and created a barrage on the prisoners there, as they erroneously thought one of the armed convicts was there.

After drilling holes in the prison roof, they dropped grenades in to try to force them into a utility corridor and corner them. Cretzer made the statement on May 3 that he would never be taken alive, and that night, the Marines fired a constant fusillade at the cell block, and armed officers rushed the cell house repeatedly. On May 4, officers entered the corridor where they found Cretzer, Coy, and Hubbard. Miran Thompson and Sam Shockley were executed on December 3, 1948, while Carnes received an additional life sentence. Later, he was released. After breaching parole, he was sent back.