I think he gave up his rights when he became a traitor.
Obama never even charged him as "a traitor". He just killed him, period, for any reason he wanted -- no charges, no anything, no defense possible, just "you must die" for any reason I want because I'm the president & my advisers said that I can get away with it, politically.
This time he may have been right because the guy was scum -- but the legal precedent has been set.
So, if Obama decides that you belong on that list one day, good luck!