Good point, and I understand where you're coming from. Then again, a body that's extremely recently dead isn't significantly different in terms of pressure or temperature from one that's alive. So long as the blood hasn't had sufficient time to congeal or begin postmortem lividity, oxygen is still present in the tissue, and the body retains pressure. The data would still be extremely useful, and they wouldn't have to go to the expense of performing physical examinations on the condemned prisoners.

Or not.