Just how does a person get put on a CIA/DOD kill list rather than being put on trial? Well:
American militants like Anwar al-Awlaki are placed on a kill or capture list by a secretive panel of senior government officials, which then informs the president of its decisions, according to officials.
There is no public record of the operations or decisions of the panel, which is a subset of the White House’s National Security Council, several current and former officials said. Neither is there any law establishing its existence or setting out the rules by which it is supposed to operate.
A secret panel writing up a secret capture list would be one thing. You could capture people, and then they could have a trial such that if they were innocent of any crime, they’d go free. But a secret kill list based on secret evidence considered in secret through a secret process from which there’s no appeal and after which you’re dead is problematic in a very fundamental way.
Let’s hope the new round of Nobel Peace Prize winners manages to do better than this.