After the Cheney shooting accident I got to thinking, obviously his Secret Service team was there when it happened. What if it hadn’t been an accident and Texas wanted to get evidence of his crime. Could they call his bodyguards to testify as to what happened?
If the Secret Service sees the President or VP commit a crime do they have to come forward? (I think the answer to this is “No,” since they didn’t stop or comment on the Bush girls’ under-age drinking a few years back.)
They don’t have to come forward but they’re amenable to subpoena just like anybody else. During Monicagate, every living president asked the courts to create a privilege for Secret Service agents to stop them testifying, claiming that because of the ruling allowing such testimony, presidents would send their detail away when in sensitive meetings. No dice.