There were surely NOT three convictions under military trials....

[On 13 June 1942, 4 agents were landed from U-584 on Amagansett, Long Island, New York; and on 17 June 1942, 4 agents from U-202 were landed on Ponte Vedra Beach, south of Jacksonville, Florida. A subsequent military trial of the 8 captured agents resulted in 6 death sentences, one life imprisonment and one 30-year sentence. On the recommendation of the Justice Department, President Truman granted executive clemency on condition of deportation to the two surviving agents who were deported to the American Zone of Germany in 1948].

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So you're relying on phony information.