Excellent post DandyDon. I will add it to the issues thread. Indeed - I did believe that Gabe's computer was a wireless Oceanic DataTrans and I posted a links to the manual about that computer here:
http://www.scubaboard.com/forums/5411863-post57.html
Here is an excerpt from the manual:
Page 12 - "During diagnostic mode (power-up) the DataTrans measures the battery volage level of both the display module and the transmitter to determine whether there is sufficient voltage to complete a full day of diving. Warning - If either or both of the Low Battery icons remain on display following activation, Oceanic strongly recommends that you DO NOT dive until you have obtained battery replacement. If there is not enough battery voltage in the display module to complete a day of diving, the DataTrans will either deactivate itself or not activate at all.
If there is not sufficient voltage in the transmitter to complete a full day of diving, the link icon and tank pressure of "00" PSI will flash on display, indicating that the display module is not receiving a signal."
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NOTE: if the battery was in the transmitter backwards, the dive computer would have behaved as indicated in bold above]. So, the manual says it will flash, but no mention of beeping. But hard to argue with the manufacturer if they say it will beep. However, even if it doesn't beep, I don't think the prosecution can make an effective argument that Watson was lying. Beeping, flashing, many of us would not necessarily distinguish.
Here is another item of note on this:
Source:
http://www.townsvillebulletin.com.au...0135_news.html
[AMANDA PHILLIPS] Mrs Phillips said in the days leading up to the wedding the pair had run errands, including picking up a dive computer that needed checking before the couple's trip to Australia. She said she thought it was Tina's dive computer, but it turned out to be Gabe's; and that the man at the dive shop said the batteries were in backwards, and turned it on to show them it worked. "Back at the house ... Tina was razzing Gabe about it, as it was usually him giving her a hard time about being a ditzy blonde and doing things wrong, but this time it was him," Mrs Phillips said. "I remember Gabe then fiddled with the dive computer for a few minutes while we were getting the rest of Tina's dive gear together for him to pack."
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From DandyDon's post above, excerpt from Watson's statement to police:
Detective Gehringer: "Have you put a battery in wrong before?"
Watson: "Yeah . . . and I changed both the batteries before I left [the US] and I basically just stuck them in."
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So - the prosecution would probably have to argue that Watson wasn't lying about the battery in backwards, but he deliberately manipulated the dive computer to create the problem. Watson's "plan" would then become even more planned. Not saying that this would be a successful argument with the jury, just putting forth what they might argue, assuming the two witnesses testify as quoted.
In addition, you would have to assume that the Australian police did not consult with an expert on dive computers. Just who did they have examining that piece of evidence? If they were so inept at examining that evidence, what about the assertion that Gabe's computer did not show an attempt to go down after Tina, as the police asserted? Certainly, they released all this evidence as fact to the public in numerous stories. I think the prosecution will have to re-examine all the computer evidence with real experts. They will not be able to rely on the work that was done in Australia.