Alabama Attorney General Troy King said Friday he would seek a capital murder charge against an Alabama man who is imprisoned in Australia after pleading guilty in the drowning death of his wife during a honeymoon scuba dive there.

King announced he would pursue the capital charge, which carries a possible death sentence, just hours after an Australian appeals court increased the sentence for Gabe Watson from one year in prison to 1 1/2 years behind bars.

Watson, 32, pleaded guilty to a manslaughter charge earlier this year in the death of 26-year-old wife Tina Watson during a scuba diving trip in Australia in 2003. He was an experienced diver while she was a novice; they had only been married 11 days when she died.

Prosecutors in Australia charged Watson with murdering the woman by turning off her air supply and holding her underwater as they dove on the Great Barrier Reef. Watson pleaded guilty to the lesser charge in June and received a one-year term, angering Tina Watson's family.

Australian prosecutors appealed and a court agreed to lengthen the term. But in a statement, King said Watson's punishment still wasn't severe enough.

"Tina Thomas Watson and her family have been deprived by the Australian court system of the justice they deserved," King said.

An attorney for Watson, Bob Austin, said the U.S. Constitution bars trying someone twice for the same crime. States can prosecute people for crimes committed outside the United States only if a foreign country refuses to bring charges, he said.

"That's not what happened here," he said. King, Austin said "can say whatever he wants."

King aide Chris Bence said there was no "international standard" on double jeopardy, or prosecuting someone twice for the same offense, and Watson didn't plead guilty to murder.

"We feel we will be able to prove he plotted and planned the murder in Alabama, which gives us jurisdiction," said Bence.

King said he had instructed his investigators and prosecutors to begin gathering evidence that can be used to ask a grand jury for a capital murder indictment.

In the written decision extending Watson's sentence in Australia, Chief Justice Paul de Jersey said he favored at least doubling Watson's 12-month sentence because he contributed to his wife's death in "criminally derelict circumstances."

But, de Jersey wrote, he agreed to extend the sentence by just six months because one of the other justices had dismissed the appeal, and the third would only agree to increase the penalty by that much.