The federal government is acknowledging that international tax evasion is a serious problem following the release of leaked documents that reveal the identities of 100,000 people around the world who hold offshore accounts — 25 of them who live in Calgary.

It's not clear whether any of the people on the list, including 450 Canadians, have actually evaded paying any tax. Jack Mintz, with the University of Calgary's School of Public Policy, says people shouldn't jump to any conclusions.

"A number of them may be fully reporting their income," he said. "Just because they're on a list with some bank account in the Cayman Islands, doesn't mean that they may be cheating."

But some, like Diana Gibson with Canadians for Tax Fairness, says it's in the best interest of all Canadians for the government to find out.

"Alberta, in their recent budget, is cutting extended health benefits for families with children with disabilities, meanwhile large corporations and wealthy individuals are offshoring their money," she said. "So this is something Albertans should be up in arms about."

Since 2006, the federal government has assessed nearly $5 billion in unpaid tax revenue from offshore accounts.

Mintz says Ottawa needs outside help in order to stop this crime.

International co-operation needed

"To really achieve anything you have to have international co-operation, and sharing of information by governments," he said. 

"It's really hard getting everyone on the same page."

Mintz says lots of countries rely on outside investment to stimulate their economy and often promise banking secrecy as a lure.

In last month's federal budget, Finance Minister Jim Flaherty promised to set up a system for tipsters to report offshore tax cheats.

Informants would get 15 per cent of the recouped tax in cases where the Canada Revenue Agency recovers more than $100,000.

The government estimates it could recover hundreds of million in revenue, but the challenge may be getting the CRA to combat tax evasion at a time when it is facing federal budget and staffing cuts.

If you have more information on this story, or other investigative tips to pass on, please email investigations@cbc.ca. You can also send mail to: CBC Investigations Unit, 205 Wellington St. W., Toronto, Ontario, M5V 3G7