The prosecutor had to prove beyond reasonable doubt that it was NOT self defense. Good luck proving a subjective negative. After I learned that particular I just awaited the official aquittal.
I assumed it was similar to a "not guilty by reason of insanity" plea, where you admit you committed a crime but there are special circumstances (that you have to prove) that mitigate it. You can't just stay silent the entire time and force the prosecutor to prove you were insane - you have to actually provide some evidence you were insane.
Is this not true?
People claim self-defense all the time, it rarely works. In this case, where the clear, legally defined standard of self-defense was met, Kyle walked.
An alternative equivalent would be if Arbery was successful at taking away the firearm and killing his attackers.