Here's what bugs me about this thing.
Number 1, it was first reported over 24hrs after the incident occoured. Number 2, Cheney was back on his way to washington when the story was reported.
Number 3, (the big one) the man was shot in his face and chest. Not face and back, that means that the man was facing cheney, and cheney shot the gun around the man's head-level. If your hunting birds why are you shooting down at neck level??? What happened, cheney hears a noise behind, spins around and automatically pulls the trigger while pointing his gun horizontally??? Call me a conspiracy theorist but something isn't adding up right. I mean, the guy is about 6 feet tall, and is over 30 yards away if you have any up angle at all the trigonomerty just doesn't work out. I did the maths, if you have a right angle, with the base at 90 feet (30 yards) and the height at 6feet (target) you need to be shooting at a 3.8140748342903 degree angle above horizontal. That's assuming cheney was prone

if they were both the same height it would be a straight shot

Usually birds fly up not down!