MONTREAL -- The family of a Canadian geologist jailed in Dubai on fraud charges is cautiously optimistic he'll be exonerated in a court hearing scheduled for Tuesday.

Andre Gauthier has been detained off and on in the Middle East since December 2015, according to his son, Alexis.

Alexis told The Canadian Press in a phone interview Monday from Quebec City that his father's troubles began when he alerted authorities in the United Arab Emirates to irregular dealings in a gold-trading company called Gold AE.

Instead of being thanked for the information, Alexis says Gauthier was arrested and charged with committing the fraud he uncovered.

Radha Stirling, with the UK-based legal specialist group Detained in Dubai, says what allegedly happened to Gauthier is common for foreigners in the UAE.

Stirling was contacted by Gauthier's family at the beginning of his ordeal.

"It's a common problem," Stirling said in an interview Monday from London. Stirling, a human rights advocate, began working for foreigners trapped in Dubai 12 years ago and has since expanded her work to other countries in the Gulf region.

"People find themselves in companies, or are expats hired to do a particular job, and if there is an underlying scam (the companies) try and use the foreigners as a scapegoat," she said.

Stirling says the Quebecer from the Saguenay-Lac-St-Jean region was a "whistleblower" who was set up by the people who committed fraud against the gold company's investors.

Gauthier, 68, was jailed in Dubai without charges for about 18 months, beginning in December 2015. He was released but then convicted on fraud-related charges and sentenced to eight years in prison, Alexis said.

He appealed, but fled the country before the appeal was completed and was caught in Oman. Gauthier was extradited to Dubai in May 2019. Alexis said since then, the court named an expert witness who came back with a report that vindicates his father.

"We received the report in November and gave it to the judge," Alexis said. "The judge said he would have a final decision (on the appeal) Dec. 24."

Alexis said his father is also facing civil court cases, "but the lawyers said they will hopefully fall with the criminal complaint."

Both Alexis Gauthier and Radha Stirling commended the Canadian government for its help in trying to secure Gauthier's release. Stirling said federal official are "very hopeful" Gauthier will be exonerated on Tuesday.

Former foreign affairs minister Chrystia Freeland called Gauthier before recently handing over her portfolio to the new minister, Francois-Philippe Champagne, Alexis said. And Alexis said he spoke with Champagne last Thursday.

"We are confident," said Alexis. "But we don't want to have high expectations. We don't know why the verdict would be negative, but so many strange things have happened that we are trying to stay realistic."

This report by The Canadian Press was first published Dec. 23, 2019.