Jane Doyle is one of four people charged with murder in the killing of Harry Doyle, who was shot five times in Surigao City on Aug. 12.
Three men have also been charged, including one who was reportedly Harry Doyle's driver and bodyguard and lived at Jane's Lodge, a resort owned by the couple in the Philippines.
"The motive, according to the results of our investigation, is the property, the money, the insurance that the deceased had," said Rose-Marie Almazan, a police investigator in the Philippines.
There are reports that Doyle's estate is worth $1.6 million.
Doyle, 62, had two last wills and testaments — one in Canada and a newer one in the Philippines, said Almazan.
"There was a big change in the last will and testament here in the Philippines," she said. "There is no other sole beneficiary of all his properties except his wife. Even his two sons are not indicated among the beneficiaries."
Doyle has a 12-year-old son with Jane Doyle, a Filipina, and an older son who lives in the United States from a previous marriage.
"It's been a nightmare with no end," Harry Doyle's sister, Anne Doyle, told CBC News.
She said she is happy police in the Philippines are making progress in the case, but officials do not know Jane Doyle's whereabouts.
The three men accused in the case are also residents of the Philippines and are all still at large.
Investigators believe Jane Doyle is currently in Canada, possibly Fredericton.
A court in the Philippines will decide whether to issue a warrant within 30 days, said Almazan.
Officials may then use the warrant to try to extradite her back to the Philippines.
"Then we will send a copy to the Canadian Embassy and to the Canadian police so that they could hold Jane there and return her to the Philippines to face the [charge] against her," Almazan said.
Harry Doyle had been living in the Philippines for several years.
Police say he was drinking a beer at a beach resort on Aug. 12 when he was approached by two men, who apparently asked for money.
An argument ensued and Doyle was shot five times before the two men fled on foot.
Jane Doyle told CBC News on Aug. 14 that her husband was shot in front of her and their children.
"It's very hard for me. It's like you eat something that you never digest. So I feel terrible and I'm very, very sad. It shouldn't happen to anybody what happened to me and my husband," she said during the telephone interview from Surigao City.
Doyle posted on his Facebook page in February that he had survived an attempt on his life.
Doyle had a picture of himself on the social networking site with the apparent bullet hole in a window behind him.
There is also a separate photo album, named "murder attempt," with 11 photographs of the bullet hole.
"I told my sister two years ago I would be murdered for being a good guy," Doyle had posted on his Facebook page on Feb. 4.
"Everyone carries a gun here," he wrote.