Can Shots Be Heard While At The Blue Hole

It is a fact that was proven by the states own witnesses that Casteel was at the blue hole that day. Sneed has to admit that Casteel would not have heard shots while at the blue hole according to the tests he done in his investigation. Now Sneed tries to explain this away by stating the water was up at the time. One big problem with this scenario, this would have been very important information to know. So why did he not retest this? Because he knows you cannot hear gunshots at the blue hole.