I was reading the Wikipedia page on the USS Indianapolis and found this particular part fascinating...
"Captain Charles B. McVay III, who had commanded Indianapolis since November 1944, survived the sinking and was among those rescued days later. In November 1945, he was court-martialed and convicted of "hazarding his ship by failing to zigzag". Several things about the court-martial were controversial. There was evidence that the Navy itself had placed the ship in harm's way, in that McVay's orders were to "zigzag at his discretion, weather permitting". Further, Mochitsura Hashimoto, commander of I-58, testified that zigzagging would have made no difference.[26] Fleet Admiral Chester Nimitz remitted McVay's sentence and restored him to active duty. McVay retired in 1949 as a rear admiral."
How did they get a testimony from Mochitsura Hashimoto, and was this common to get a statement from the enemy after ships were sunk?
How did they get a testimony from Mochitsura Hashimoto
Well, November 1945 was two months after the end of the war. By that time Mochitsura Hashimoto was in Allied custody.
was this common to get a statement from the enemy after ships were sunk?
Captain Charles B. McVay III was the only USN ship commander to be court-martialed for the loss of his ship during the Second World War. I don't think you could say it was common.
Occasionally members of armed forces have testified for former enemies. Famously, Admiral Nimitz testified for Admiral Doenitz at the latter's trial for conducting unrestricted submarine warfare.