We should not bash Mesa but we should be bashing the FAA for dropping the ball on this. Yes it is the FAA's fault. The NTSB has recommended many times to the FAA that a change in rest rules is due. It is on their top list of safety improvements for the airlines.

Per Mesa SOP those two pilots were probably over worked and on the back side of the clock and the only thing they should be faulted with is NOT calling fatigued.

This should be a lesson to everyone that while you might be harassed into not calling fatigued, the company would surely fire you for falling asleep, and I am not just talking about Mesa but any airline. So the sure bet is if you are tired is just call time out because it beats getting fired.