In 1961, Cohen was again convicted of tax evasion and sent to Alcatraz. He was the only prisoner ever bailed out of Alcatraz; his bond was signed by U.S. Supreme Court Chief Justice Earl Warren. After his appeals failed, Cohen was sent to a federal prison in Atlanta, Georgia. His heavily armored Cadillac from this period was confiscated by the Los Angeles Police Department and is now on display at the Southward Car Museum in New Zealand. On August 14, 1963, during his time at the Atlanta Federal Penitentiary, inmate Burl Estes McDonald attempted to kill Cohen with a lead pipe. In 1972, Cohen was released from the Atlanta Federal Penitentiary, where he had spoken out against prison abuse. He had been misdiagnosed with an ulcer, which turned out to be stomach cancer. After undergoing surgery, he continued touring the United States and made television appearances, once with Ramsey Clark.