A judge expects to sentence David Swain on Nov. 4. He faces life in prison and would be sent to a Tortola prison where he has been held for about two years.
Swain did not react when the verdict was read. The parents of the victim, Shelley Tyre, gasped.
After obtaining permission from the judge, her father, Richard Tyre, walked to the witness box and clutched a microphone. "We're old, we're in our 80s, and when Shelley was killed, our life pretty much ended," he said in a broken voice. He then left the courtroom.
The nine jurors had four hours to produce a verdict under local law. Although only a seven-vote majority was required, Supreme Court Justice Indra Hariprashad-Charles urged the seven women and two men to issue a unanimous verdict after giving a three-hour summation of the case, and they did.
Defense attorney Timothy Bradl, of the Boston-based firm Denner Pellegrino, said the verdict would be appealed to the Eastern Caribbean Court. He said he noted several problems during the judge's summation, but gave no example.
Swain was led out of the British Virgin Islands Supreme Court to the flash of cameras but made no comment as he entered an armored car.
His son, Jeremy Swain, held an impromptu news conference outside the courtroom to defend his father. "My father is an innocent man," he said.
Prosecutors accused Swain of killing his wife so he could pursue a romance with a Rhode Island chiropractor as well as gain his wife's inheritance estimated at $630,000 and save his now-shuttered dive shop.
The prosecution presented experts who testified that they believed Swain wrestled his wife from behind, tore off her scuba mask and shut off her air supply while diving near a shipwreck.
The drowning was initially ruled an accident, but authorities in the British Virgin Islands charged Swain with murder after a 2006 civil trial in Rhode Island found him responsible for his wife's death. That jury awarded Tyre's family $3.5 million, but Swain filed for bankruptcy and has not paid the sum.
Swain was extradited to the British Virgin Islands the following year and had been jailed since.
Defense attorneys maintained the poorly done autopsy report could not rule out medical reasons for Tyre's death, including the possibility that she suffered a heart attack or stroke during what they say was an accidental drowning.
The trial, which began nearly three weeks ago, was postponed last year after defense lawyers said they had trouble finding experts because of financial constrictions.