This aired on Dateline NBC on Friday, Dec. 18, 2009. The full video won't be online, but you can watch related web-exclusive clips here.
When a frigid New England winter refuses to loosen its grip, and slush weighs down the soul, there is an antidote waiting for the lucky few: the bathtub warm waters of the Caribbean.
Swim. Sun. Sail. Repeat, until the back up North stress melts away.
Better still, slip into an azure sea and have a look around at an underwater world that divers say is like a parallel universe.
Bob Brousseau: It's a majestic world. It's just awe-inspiring.
BetsyDake: It's incredibly peaceful. You're down there with the fish. You look around you, and there's amazing wonder. And the closer you look, the more beautiful it gets.
DonLockard: It's exhilarating. I'm always on pins and needles when I get out of the water.
Shelley Tyre and David Swain shared that passion for scuba diving, so to escape a dreary Rhode Island winter in March of '99, they chartered a 40-foot sailboat with another couple. If a fancy-free scuba vacation is what you want, it doesn't get much better than the British Virgins.
KeithRoyle: What they would do is sail around the area to the different islands, stop where they wish, do a dive or two and then move to a different island.
She liked to count fish underwater. He liked to photograph them. So what could go wrong? As it turned out, quite a lot.
They were wreck-diving south of the island of Tortola when it happened.
Dan O'Connor: He noticed that her breathing apparatus was out of her mouth.
KeithRoyle: I heard an emergency call that there was a diving accident and they needed assistance.
Policeman: The body appeared to be lifeless.
What happened in thirty minutes' time, eighty-feet beneath the surface, would be examined and replayed in people's minds for the next decade. How was it that an experienced diver like Shelley Tyre could be lost just like that? And when it happened, where exactly was her husband, a master dive instructor who was her safety buddy on that dive?
He would end up telling the story of that horrendous day in a taped deposition, but he'd start by telling the story of David and Shelley -- how they met, in the early nineties. The instructor and the dive customer.
DavidSwain: We went kayaking in Narragansett Bay.
Police: Anything unusual about that trip that you remember?
DavidSwain: I suggested that we come in because it was a little rock-and-roll weatherwise, and lightning and thunder, and she said, “No, let's stay out here, it's kind of neat and fun.”
Shelley--Shelley Tyre--was a bundle of energy, a five-feet-nothing tall teacher and school administrator. She was as vivacious as he was quiet.
David Swain: We're going to paddle out around this point.
And David was only too happy to show Shelley the waters where he pursued his life's passion: teaching scuba and kayaking through his dive shop in Jamestown, Rhode Island. Here he is in 1997, giving a kayak lesson.
David Swain: It's just a very easy figure-eight stroke...
Swain was known to his friends and customers as an honest businessman, and an active member of the community.
DonLockard: quiet guy, and honest guy. You know, somebody that i thought i could depend on and trust.
RandyWietman: If you wanted help with something, he was always there.
BillMunger: He's sincere. He cares about other people. He's always looking to make the world a better place.
And, likewise, the people in Shelley's circle raved about her. School parents like Colleen Tondorf.
ColleenTondorf: She was effervescent. She was always on the move, always on the go.
Shelley -- who famously wore a bumble-bee costume to a school event once -- was seen as nothing less than a gift by the faculty and parents at Thayer Academy in suburban Boston where she was headmaster of the Middle School.
ColleenTondorf: She had an ear for every child. And when she spoke to you, she looked you in the eye. And she didn't care. The world fell away. She was there focused on you and listening to what you had to say. It was great.
And always by Shelley's side, constant companion Tori the Bernese Mountain Dog. Her furry comfort was always available to a pupil having a bad day.
Dennis Murphy, Dateline NBC Correspondent: And, of course, Tori is in the yearbook.
ColleenTondorf: Yes. when you look at faculty--
Dennis Murphy: And it's not just a joke or anything--
ColleenTondorf: No, no, no. As faculty you have Shelley Tyre, Tori Tyre. You know, two separate pictures.
Shelley and David married in 1993. They didn't have children together, but she quickly endeared herself to his two, a son and a daughter, from a previous marriage.
Shelley became actively involved in David's dive shop -- planning the big expansion to add a pool so he could teach diving year round.
The fly in the ointment was Shelley's weekday commute. The private school where she worked was a long slog from coastal Rhode Island. She was probably seeing more of Tori the dog than David her husband.
Dennis Murphy: How long was the commute? How many hours a day?
ColleenTondorf: I think it was some god awful amount.
Dennis Murphy: At least four hours behind the wheel back and forth, huh?
If Shelley's life as a road-warrior was stressing the couple out, those who knew them reasonably well, like Marina owner Bill Munger, didn't see it.
BillMunger: We'd see Shelley and David on a Saturday morning. You know, having coffee together across the street. So, I mean, they were, I mean, a natural, loving couple.
Dennis Murphy: But everything seemed to be okay when you saw 'em around town--
BillMunger: Everything seemed to be fine.
Spring break of 1999 would be Shelley and David's time to escape the grind and enjoy together what they loved best -- the water.
Dennis Murphy: So come spring break that year, she and her husband David are gonna go to the British Virgin Islands and dive.
Dennis Murphy: She was going to be identifying fish?
Dennis Murphy: In one of the most beautiful oceans of the world?
But, of course, that trip -- that last dive -- would go so horribly wrong. How could anyone make sense of the deeply sad and mysterious death of Shelley Tyre?
ColleenTondorf: She was looking forward to this dive. She thought it would be beautiful, a place that she had anticipated going. She had books in her office on it.
Tortola, the British Virgin Islands: sailing, diving, postcard-perfect beaches--how Shelley Tyre looked forward to it! She and her husband David had chartered a sailboat with their friends, the Thwaiteses. The other couple would be bringing along their young son. A week of diving and sailing, whichever way caught their fancy.
Upon arrival here on Tortola, the men set about to arrange for their charter and the rental of their scuba gear. The women went shopping for provisions for their sailboat, called "The Caribbean Soul." Then the five motored out from this marina for their holiday at sea. To this day, no one in that group can say that anything was amiss.
And it was, by all accounts, the leisurely week gunk-holing around the Caribbean that all on board had hoped for. They dove the British Virgin's greatest hits: Salt Island, Peter Island, the Wreck of The Rhone.
On the morning of March 12th, they set a course for Cooper Island, and a site known as the Twin Wrecks. Tortola dive instructor Keith Royle has been down to the Twin Wrecks hundreds of times.
Keith Royle: There are two wrecks sitting right next to each other-- bow to stern, and there's a small gap in between them. The allure to that is the fish life. And also you have a reef right next to the twin wrecks, so you've got the best of both worlds.
David Swain and his friend Christian Thwaites were both certified scuba instructors. Between them they had more than a thousand dives under their belts. And Shelley Tyre was no novice: in her log book, she'd reported more than 350 dives. Now, divers with comparable experience will tell you that diving the Twin Wrecks Sit - with its nice, flat sandy bottom, great visibility and minimal currents - is about as challenging as a walk in the park on a sunny day.
At about noon that day "The Caribbean Soul" tied-up at the Twin Wrecks, nabbing the sole mooring. In a sometimes busy tourist ocean, the friends on board would have the dive site all to themselves. It was decided that Shelley and David would go down first -- sticking to the scuba diving "buddy system" of always diving with a partner. Then they mapped out a dive plan.
Interrogator: What was that?
David Swain: That we'd stick together getting down to where it was we wanted to go, and then after that, she'd go off and do her reef fish survey count, and i'd go off and take pictures.
David Swain described that day four years later for the record. That fateful final dive of the vacation -- the one where he came up, and she didn't.
Interrogator: On the fatal dive, who entered the water first, you or Shelley?
David Swain: I don’t remember.
David Swain says he and Shelley made their way together over the reef and across the open sand, to the Twin Wrecks dive site.
David Swain: I have a vague memory of swimming around it slowly and poking in the openings here and there.
Interrogator: Did you swim all the way around the wrecks?
David Swain: probably. I don't recall for sure, but probably.
Interrogator: How much time did you spend at the wrecks?
David Swain: not long. Certainly less than ten minutes, probably more than five.
Voice: after your five to ten minutes at the wrecks, what did you do?
David Swain: meandered over towards the reef area to see if there was something there to see.
And Swain says that's when he got separated from Shelley.
David Swain: Have a vague recollection of circumnavigating the wrecks, poking around the wrecks, and seeing Shelley still interested in looking at something around there, and that's the last time I saw her, as I swam off towards the reef.
Interrogator: Have you thought about the last view you had of Shelley?
David Swain: Considerably.
Interrogator: Tell me what you recall seeing?
David Swain: A gal in an environment, contented to be there, just as normal as ever.
But somehow--at some point in what should have been a placid dive--something went horribly amiss. David Swain says he surfaced from his dive, alone.
Interrogator: Did you ask about Shelley?
David Swain: I probably did a "Has anybody seen Shelley yet" and they probably said "No, not yet."
No one thought much about it at the time. Christian Thwaites, then, started his dive. Thwaites would later give a statement that between the anchor line and the wrecks, he found something odd -- Shelley's fin, like this one, sticking up out of the sand. When he got closer to the Wrecks, he found Shelley herself lying on the ocean floor, face up, eyes open, near one end of boats. He quickly grabbed her and brought her to the surface.
Interrogator: When Christian came to the surface, what did he say?
David Swain: I think he used the word emergency.
Interrogator: And you did what?
David Swain: Got into the dinghy and motored over to where he was.
Interrogator: And were you then able to observe what about Shelley as you got even closer?
David Swain: That she was in some kind of trouble.
Christian and David say they both attempted CPR, but Shelley's lifeless body gave no response. David
Interrogator: When you got Shelley's body to the boat, you already thought she was dead?
David Swain: Yes.
Back on the boat, Swain radioed for help. The first to respond was Keith Royle.
The scene on "Caribbean Soul" was somber. And Shelley was laying in the cockpit, and everybody obviously was very, very distraught.
Keith sped Shelley to Tortola's harbor, David Swain beside her in the back of the boat. Swain, still in his wet suit, was met at the local hospital by Tortola police.
Jones: I can remember that he appeared saddened. He pointed out to me the body of a Caucasian lady in one of the beds there at casualty. He indicated to me that that was in fact his wife.
An autopsy was conducted at a local funeral home. The cause of death: drowning. The medical examiner called it an accident. Swain was free to leave Tortola and return to his own little island of Jamestown. To settle back into the routine of running his dive shop. But without his Shelley Tyre, his wife of five and a half years.
But years later, he would return to Tortola, this time, in handcuffs.
Colleen Tondorf: We came home and looked at the phone and saw there were 12 messages. And I immediately thought, "It means somebody died."
Dennis Murphy: How did you take the news, Colleen?
Colleen Tondorf: Oh, I cried for three months in a row. It was hard. It's a hard thing to think that that could happen to someone.
And not just anyone, but someone so full of life as vivacious, energetic Shelley Tyre. What had happened to cause her to drown while scuba diving off the Caribbean island of Tortola? Back home in Jamestown, Rhode Island, the newly widowed David Swain - in his typical close-to-the-vest style - shared few details with friends like Bill Munger.
Dennis Murphy: Do you remember the first time you see him or what you said?
BillMunger: Yeah, I gave him a hug. And you know, there was tears -- both of us.
And around town, David Swain seldom spoke about his wife. Rather, he just packed up her stuff, sold their house, and gave away her beloved dog, Tory.
Was David Swain trying to erase Shelley Tyre from his life? Just wipe the slate clean? Or was he trying to grieve in the only way that he knew how? Then again, did perhaps something very dark happen here in the Caribbean?
The story: How she was found, missing some diving gear. Some thought it didn't add up. Was it even possible that Swain had had had something to do with his wife Shelley's death? The rumors took flight.
Dennis Murphy: Was the town divided then?
BillMunger: Certainly if you went up and down the avenue here you would find, people on both sides of the issue.
And if the whisperers huddling at the local coffee shop would stop and "look busy" when David Swain walked in, it didn't seem to much phase him. Just two months after Shelley's death, he ran for Jamestown's town council and won.
Dennis Murphy: Why do you think he got into politics?
BillMunger: I think just to try to make the community a better place, simple enough. I mean, there's no money in it.
But Swain did have one new alternative source of money -- he would collect more than $600,000 in life insurance and other assets of Shelley's.
And two town council votes he probably get didn't were from Shelley Tyre's parents, Richard and Lisa. Ever since Swain had returned from Tortola with their daughter's body, the Tyres wanted answers from their son-in-law. Answers they weren't getting.
Richard Tyre: The first moment I heard it, I kept saying over the phone to him, but you had the buddy system, you were there, you had the buddy system, you were there! And he kept saying, “I wasn't there.”
By 2002, the Tyre family's suspicions had festered into full-blown accusations. Three years after Shelley's drowning, the Tyres filed a civil lawsuit charging that David Swain was responsible for Shelley Tyre's death.
Attorney: We believe there's overwhelming evidence as i put in this complaint that he committed this murder.
The Tyres hired experts to thoroughly investigate Shelley's drowning. After travelling to Tortola and examining Shelley's scuba equipment, the experts formulated this scenario which they then re-enacted on videotape ... that David Swain attacked Shelley underwater: approaching her from behind, shutting off her air supply and then holding her down until she drowned.
A shocking allegation which was never challenged because David Swain chose not to appear in court. Nor was there anyone else in court representing him, because his cancer-stricken lawyer had had to bow out before the trial began.
At the end of the trial, though, David Swain did make a surprise appearance -- and a last-ditch effort to defend himself.
David Swain: It's a grand story, but it's just not true.
Swain said his wife's death was a "tragic accident," and called the attack scenario a "fantastic story" "fabricated" by the plaintiff's experts. He then called a single witness to the stand -- his daughter, Jennifer.
Jennifer Swain: You told us this story about Shelley's drowning. You were tearful, and angry.
But it wasn't enough. David Swain was found responsible for Shelley Tyre's death. The jury awarded her parents $3.5 million.
Lisa Tyre: We have now found out what we wanted to find out. What exactly happened.
Swain, in turn, spoke out to the local news, about Shelley.
David Swain: She was just a good, all-around great person.
About not knowing why Shelley died...
David Swain: There aren’t many but there are some situations where there are some people in whatever they do, they just perish. It's not right, but it happens.
... and about his innocence.
Reporter: Did you kill your wife Shelley?
David Swain: Absolutely not.
The friends who'd stood by him throughout were shocked by what they saw as a miscarriage of justice.
Bill Munger: I think everybody expected that that trial wouldn't go anywhere because there was no cross-examination. Nothing went on, it was totally a one-sided trial.
But that trial could - by and large - be shrugged off, because it was only in civil court, where the burden of proof is much lower than in the criminal system. Plus, David Swain couldn't pay the Tyres anyway -- he'd already filed for bankruptcy months before.
But that civil verdict did catch the attention of authorities a world away, down here in Tortola, in the British Virgin Islands. Officials here had ruled Shelley Tyre's drowning an accident back in 1999. But the fine print read accident "unless proven otherwise." The judgment in civil court against Swain had given them prosecutorial ammunition.
Tortola reviewed the evidence from the civil case, and made an extradition request. Eight years after her death, U.S. marshals showed up at the dive shop and arrested Swain for the murder of his wife Shelley Tyre.
Local reporter: Swain is being held without bail.
RichardTyre: This is almost a miracle that this has happened. His attorney told me swain is confident, in a good mood, and anxious to get there, and get this process underway.
This time, Swain wouldn't take any chances. He would launch a vigorous defense, but he'd now have to plan it from his new home ... a stifling cell in Tortola's Balsam Ghut prison. It's a fortress high up on a bluff facing the ocean, where the view can't be beat but comes at a price no one wants to pay. And there was no telling how long David Swain would be playing unwilling tourist.
After two years in a prison on the Caribbean island of Tortola, David Swain would finally have his day in court. The charge: murdering his wife Shelley Tyre on a scuba dive ten years before. The trial began on a muggy morning this past October. British Virgin Islands Chief Prosecutor Terrence Williams would try the case.
Mr. Williams: Well-- first struggle is understanding diving.
Dennis Murphy: Are you a diver yourself?
Mr. Williams: Oh, not at all.
Shelley's parents attended the trial, as did David Swain's son and daughter. And with the stakes so much higher this time -criminal - not about money but maybe decades in prison - Swain came prepared. He'd retained attorneys from a top Boston law firm, plus Caribbean counsel to present his defense.
With everyone in place, David Swain himself was brought in, showing every bit how two years in a hot Tortola prison can age a man. You had to squint to see the onetime affable scuba instructor who'd pleaded Not Guilty.
Reporter Dan O'Connor covered the trial for the BVI Beacon.
Dan O'Connor: There's no communication between the two families. And that division tells a lot about the feeling in the courtroom.
No cameras were allowed in court, but the press could audiotape the proceedings. Prosecutor Williams laid out his case to the jury methodically, speaking first of motive:
Prosecutor: This man here, his wife is killed, and all his dreams came true. All his dreams came true.
Dreams, he would argue, about money -- more than $600,000 -- and another woman in Swain's life.
A lethal scheme executed, he said, in an underwater setting. The autopsy had shown no underlying medical reason for Shelley to have drowned. So the key to what DID happen to Shelley Tyre, the prosecution said, was her diving gear, how it was damaged.
Her snorkel -- missing its mouthpiece. The strap to her mask -- broken ... the pin that held the strap in place, gone. That kind of damage happens rarely in the world of scuba, experts said, and only when great force is applied to the equipment.
Prosecutor: They have never, ever seen this strap broken like this during a dive, never, ever!
And what about Shelley Tyre's lone fin, all by itself stuck in the sand, toe-first, its heel strap pulled back? The prosecution said it could have ended up in that position if Shelley's foot was yanked out of it as it was forcibly shoved into the sand. The prosecution put forth the same theory advanced by the civil attorney back in the 2006 Rhode Island trial -- that Shelley's scuba gear in such disarray meant only one thing: that Shelley Tyre had been attacked underwater.
Prosecutor: What this shows is a continued struggle with a human being.
And the only human on that dive with Shelley? Her husband and dive-buddy, David Swain.
Swain's innocent version of the dive was the account he'd given in a sworn deposition for the wrongful death suit in 2003.
David Swain: I have a vague recollection of circumnavigating the wrecks, poking around the wrecks, and seeing Shelley still interested in looking at something around there, and that's the last time I saw her, as I swam off towards the reef.
No way, countered Prosecutor Williams. It couldn't have happened as Swain said it did. And here's why, as laid out by scuba experts.
First, the pressure gauge on Shelley's tank showed she'd used just under one-third of her oxygen on her dive ... which the experts said meant she had breathed air underwater for only eight minutes before she drowned, right near the Twin Wrecks where she was found.
The experts then said that given Swain's description of his dive, at eight minutes in, Swain would have been right where Shelley was -- right when she was drowning.
Prosecutor: Obviously he was there with her! And further, it goes to tell you that when he swims away, according to him, and looks back and sees her and she's fine, that cannot be true!
So why'd he do it, the Prosecutor Williams asked? For one thing, money.
The Tortola jury was given what the prosecution regarded as an important fact, and it had to do with an agonizing lifestyle change that Shelley Tyre had made just before that spring break vacation. She was going to quit the job that she loved so much at the private school and take a job at another school. It was a school closer to her home, but it was also a job that paid a lot less money.
And that was going to mean a big change in lifestyle for David Swain, the jurors heard. Shelley's income had been keeping the all-but-failing dive shop of David's afloat for years....but now Swain might have to put aside his life's great passion to start earning his keep.
Why would Shelley make such a radical change? The prosecution said it had to do with Swain's second motive
Prosecutor Williams: He had started to have an attraction to another woman, towards the end of the year before she died.
That "other woman" was Mary Grace Basler - Doctor Basler. She was a local chiropractor and a diver who frequented David's shop. Tortola jurors heard from Mary Basler that David Swain had tried to kiss her, during an evening drinking wine at her home -- but she rejected his advances because he was married.
Then there were the letters Swain wrote to Mary Basler, some of them before his wife's death. In one, he asks a "particular playmate" to join him in Vermont. He calls her "Soulmate Mary!" Another he signs, "With all my love ... David."
Most ominously, this one, dated five months before Shelley's death, which reads: "Life has definitely gotten more complicated ... I'm wanting to be with you but I can't change this mess I've got anytime soon."
Why not just divorce? Because their nuptial agreement prevented either David or Shelley from receiving money from the other if they parted ways. But the prosecution said Swain saw another way.
Prosecutor Williams: Under the will, if she died, he recovered-- he benefitted from her entire estate.
In fact, with Shelley gone, David would get the dive shop, the money and the girl. After Shelley's death, he collected more than $600,000 in life insurance and other payouts -- all of which he quickly spent on things like traveling and his shop. And just two months after his wife's death, he and Mary Basler started dating.
Dennis Murphy: And in fact, they became a couple following Shelley Tyre's death.
Prosecutor Williams: yes, they dated for, I believe it was a year and a bit, and then she broke it off.
Lastly Williams also brought to the stand a trio of witnesses critical to the prosecution's case: Christian Thwaites, Swain's own friend and charter boatmate who said Swain hardly attempted CPR on Shelley out in the dinghy, even though CPR training mandates never to stop until help arrives.
Prosecutor Williams: By all accounts, there was brief CPR. And--
Dennis Murphy: Brief meaning a few minutes?
Prosecutor Williams: A matter of a few minutes.
Keith Royle, who testified that when he pulled his boat up to the Caribbean Soul to offer assistance, he was surprised to be told "no thanks."
Keith Royle: He declined my offer of CPR and oxygen. And I thought it was a little strange.
Another prosecution witness was Phil Brown, the island dive shop owner who'd rented the two couples their scuba gear and who'd collected Shelley's scattered and broken equipment from ocean bottom. Brown said that swain later came into his shop after the so-called accident, and told him to give away Shelley's dive gear.
Add it up, said the prosecutor, and you had a husband who wanted his wife's dive gear deep-sixed before a proper investigation. A husband who didn't really try to revive his wife. A husband who wanted her dead.
But tides in the Caribbean, like everywhere else, run in and out. For the first time in ten years of rumors and lawsuits, a jury would hear a true defense from David Swain. And the prosecutor's account, that seemed as clear as a Virgin Island dive site, would become murky and clouded over.
Tortola Jurors in the case of the Queen versus David Swain had just finished hearing seventeen prosecution witnesses. They'd told a tale of an unspeakable underwater crime committed by a cold-blooded husband.
Now, for the first time, David Swain would launch a defense, led by his attorney, Hayden St. Clair Douglas. And the jurors would hear a different take on Swain's so-called motive.
Douglas showed the jury another letter Swain wrote to the "other woman," Mary Basler - telling her, "Our getting together actually saved my marriage."
Hayden St. ClairDouglas: David Swain did write to Mary Basler and confirm that I did take steps. I did, as a result of your rebuffing my approaches, I did take steps to work on my marriage. To come to terms with my wife, and we were on the way.
Douglas also said that Swain never really cared about money...and that there was no evidence that Shelley's paycut meant he'd lose his dive shop. The bottom line, Douglas said, is that when you looked at all the evidence, Shelley Tyre's death could just as likely be a tragic but unexplainable accident.
Defense: I do know that the possibility of homicide, that possibility is not the only possibility.
First off -- maybe Shelley DID have a medical problem that caused her to drown ... we'll never know for sure, the defense said, because the autopsy conducted on her body hadn't been done thoroughly by an examiner who was familiar with scuba deaths.
She did apparently suffer from TMJ, a condition of the jaw that can cause pain and sometimes even lockjaw, a grim prospect for a diver way down with a breathing device in-mouth.
And, Swain's defense offered, it wouldn't even take a medical problem for a pleasant dive to become a lethal accident all too quickly. Just a small irritant could, on the wrong day, make even an experienced diver like Shelley PANIC.
And it's not as far-fetched as you think. Just ask Betsy Dake, one of David Swain's many diver friends who closely followed his trial.
BetsyDake: That can happen. I've had it happen to me. It's a bad, bad feeling.
Dennis Murphy: Panicking under water.
BetsyDake: It is a horrible feeling. And you don't react calmly. You don't follow your training. If you're lucky, you don't die. I was lucky. And I think something happened and Shelley wasn't lucky.
Swain's attorney told the Tortola jury just that, that Shelley's own panic is a likely explanation for why her scuba gear was found broken and scattered on the ocean floor.
Defense in Dateline interview: One cannot accurately predict what a person might do when he succumbs to panic. But even so, it is recognized that one thing that they do do is to reject their equipment, to simply pull their masks off and that sort of thing because it is an irrational state of affairs.
The defense then read the jurors excerpts from Shelley's own dive log bookm there noting down the occasions when she'd lost it a bit to fear.
Dive 167: "some initial panic".
Dive 183: "panic"
Dive 266: "I admit I panicked"
Dive 274: "panicked a little. Or more."
So maybe Shelley's death WAS an accident, which still begged the question, why didn't Swain keep an eye out for her, not only as her dive buddy, but as her husband? Betsy Dake can explain why.
BetsyDake: I will tell you that as an underwater photographer myself, you're a lousy buddy. Underwater photographers are terrible buddies. We don't look at anything but what is in our little viewfinder. To be honest, I could have a buddy five feet away from me drowning behind me and I wouldn't know it. Because you just don't pay attention.
Could there be other innocent explanations for David Swain's actions? The prosecution had hammered away at Swain for stopping CPR on his wife too soon. But now his defense reminded the jury that as a trained EMT, Swain knew very well when a victim was beyond being revived.
Hayden St. ClairDouglas: He knew the signs that he should look for, that he did look for those signs, and that he did come to the conclusion, unfortunately, that she died.
But what about the prosecution's claim that if you believe David Swain's description of his dive, he had to have been right there when Shelley was drowning, eight minutes after she entered the water.
Now the defense said hang on: how do we know Shelley stopped breathing after eight minutes? In truth, Shelley was so tiny she was known for using less air than an average diver, which meant she likely WAS alive and well eight minutes into the dive, just as Swain had said.
Interrogator: Tell me what you recall seeing.
David Swain: A gal in an environment, contented to be there, just as normal as ever.
But what about that other confounding find? That dive-fin wedged toe-first into the sand, its heel strap pulled back. Like a key clue at an aquatic crime scene, the prosecution had surmised that the fin was a clear sign of an attack.
The defense wondered about that theory - and Dateline tested it out, conducting our own experiment down at the Twin Wrecks site with the help of Tortola diver Keith Royle.
Keith Royle: I went down in the same area and tried to do the same thing myself with the fin on, and it was impossible. The only way I could actually get it to stick in the sand was physically, with my hands, putting it into the sand.
In other words, Royle says, someone must have put it there intentionally -- but who? The defense brought all the pieces together of what could very likely have happened on Shelley Tyre's final dive -- Number 355.
She descends the mooring line ... a bruise, found later at the autopsy, had been bothering Shelley on her left foot. So she peels her fin off and sticks it in the sand to retrieve later. She nears the Twin Wrecks, and after a week of diving in a head-squeezing scuba mask, her TMJ flares up. She massages the side of her face, and and her jaw locks without warning. Now things are going wrong fast. Frustration takes hold, and mushrooms into full-blown panic. She can't tamp it down like before. Irrationally, she tears off her mask and rejects her regulator. And out of sight of her husband David, she tragically, fatally, loses control.
Next the jurors would hear from Swain himself. It was time for the man of few words to find his voice as never before.
ColleenTondorf: We really need to remember that she was this incredible life force. And she had all this energy, positive energy. So every time it came around to the criminal trial, I thought, "Please god, let somebody find a way back to letting people know how wonderful she was.
That special light of Shelley Tyre, dearly missed by so many who knew her. Was her husband, David Swain, responsible for taking it from the world? Or was he an innocent man whose private ways had made a tragic accident only look like murder? A jury in a Tortolan courtroom would soon decide, but not before David Swain himself took the stand to answer questions from his attorney.
Douglas: Mr. Swain, when you went on the dive with Shelley Tyre on that 12th of March of 1999, did you kill Shelley Tyre?
David Swain: I did not, could not, would not dream of taking the rock of my life out of the world. That's just .... No, I did not.
Douglas: Did you in any way during the course of that dive deprive Shelley Tyre of air?
David Swain: The last thing in the world is I would deprive Shelley of anything, so I certainly didn't deprive her of air.
Then it was the prosecution's turn.
Attorney: You held her down!
David Swain: I did not.
Attorney: .... And made her become unconscious.
David Swain: I did not.
Attorney: And this was within eight minutes of the dive.
David Swain: It was not. I did not. You are making false accusations.
Then, around lunchtime on the thirteenth day of trial, the seven-woman, two-man jury retired to the deliberation room to decide David Swain's fate.
Outside that closed door, the mood around the courthouse was tense, watchful.
Then, after five hours, word came - there was a verdict. Mother, father, son, daughter, all filed in...
Judge: How say you? Is the accused, David Swain, guilty or not guilty of murder?
Foreman: We, the jury, find the accused guilty.
David Swain, guilty of murdering his wife Shelley Tyre. Inside the court: tears, shock, even heated words between Richard Tyre, Shelley's father, and Jeremy Swain, his son.
Outside the courtroom, David Swain's children turned to leave, but then spoke to the cameras.
Jennifer Swain: The jury made a mistake today.
Jeremy Swain: My father's an innocent man. This is a horrible mistake. My father's life has already been ruined. Nothing further can be done to bring Shelley back, so what is the point of this?
Jennifer Swain: The memory of my stepmother can't be treated like this. We're going to appeal.
Then it was Shelley's parents turn to speak.
Richard Tyre: We're just glad people like David Swain won’t be able to hurt women any more.
The Swain family and his friends quickly filed more than 40 letters with the judge, citing David's shining character, his good heart, and his innocence. But the judge wasn't swayed. She gave him life in prison with a chance of parole in 25 years. A fate many who know David Swain consider a monstrous miscarriage of justice.
BetsyDake: Prison means that there are no other facts, there are no other explanations. Prison means that there is no reasonable doubt.
BetsyDake: Exactly. When I look at the possibilities, there's a ton of reasonable doubt.
In the past few weeks, Swain's daughter Jennifer has launched what some might call a "thirteenth-hour" offensive to help her father's appeal. She's publicly revealed intensely personal details about her father's "troubled past" as a way to explain his cool demeanor: family secrets about his parents' quarrelling and break-up ...and that his brother bludgeoned his mother to death.
Jennifer says if the Tortola jury had heard about her father's childhood trauma, then they would understand the real reason why he seemed so emotionally detached when he talked about his wife. All along the way theory goes, it wasn't David Swain's guilt we were seeing, it was memory loss from post-traumatic stress disorder.
David Swain disappeared from sight as he was placed inside a police van and driven back up the hill to the prison where -- failing an appeal -- he'll remain for decades to come.
There the smell of salt air will wash his cell, added punishment for this inmate who so loved the ocean. And now may never swim in it again.
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