Dateline NBC Story & PANIC:
I saw something in this story that I thought did not go so well for Swain. One minute the prosecution asks Swain "how did Shelley appear to you the last time you saw her?" Swain replied something like - like a woman in her element enjoying where she was. Clearly, Swain is saying she was not panicking at this point. Then, the defense shows log books that Shelley talked about "panicking". This would make a juror wonder that if Shelley did have some kind of regular panic problem, why wasn't Swain sticking with her? So it would seem that there is a contradiction. The defense was that Shelley was a perfectly comfortable diver, comfortable in her element at the time she and Swain split, but had a history of panic, but not enough where Swain needed to worry about it and stick with her. This is a contradiction that I think would be difficult for a jury to overcome.
I would say the entries in Shelley's log book were really more on the level of anxiety and not panic. She also describes in her logbook how she would see some really neat creature and forgot all about it. To me, anxiety is something you can dive through or get over just as Shelley described. Panic is where you start making mistakes and the dive goes really wrong, where you may narrowly avoid serious injury or death. I did not hear any description of such an event in Shelley's logbook.
Then, there was defense testimony about TMJ that could have caused Shelley to panic. I did some research on this. Here is a quote from an expert on the subject:
"Because Dr. Richard has specialty training in aerospace medicine, she understand that changes in barometric pressure, as associated with flying or scuba diving, can exacerbate TMJ pain.."
Source:
TMJ Temporomandibular Joint disorders Dr Patricia Richard MD DMD Facial Pain and Pain Management Connecticut
So, barometric pressure can bring-on the TMJ, but Shelley is completely comfortable and in her element for the first ten minutes of her dive, according to Swain. If barometric pressure is the catlyst that exacerbates TMJ during diving, certainly the problem would have started on the descent and not suddenly after ten minutes on the bottom. According to the same source, TMJ is often mistaken for an ear-ache, so the symptoms would be very similar to ear squeeze.
If these were the arguments at trial, I can understand how the jury would have dismissed TMJ as a viable cause of Shelley's panic. Otherwise, she was in good health, the conditions were not stressful and the rest of her equipment was in good working order. It is difficult to come up with another explanation for Shelley to have panicked. I believe it is safe to say that the vast majority of panic occurs with overexertion and overbreathing the regulator, causing hypoventilation and feeling of not being able to get enough air. This has led to reports of divers removing the reg from their mouths. However, conditions were calm that day, no testimony of fighting currents or other adverse conditions.