A Costa Rican family is leaving Toronto after three years in Canada because immigration officials say their son's Down syndrome is too much of a burden on taxpayers.

Even though they are leaving the country, they're still fighting what they call medieval and barbaric legislation because they say it may help other families.

Felipe Montoya and Alejandra Garcia-Prieto have been trying to get permanent residency in Canada since they first moved to Toronto three years ago with their two teenage children so Montoya could teach environmental studies at York University.

He was singled out solely because of his genetic identity. - Felipe Montoya speaking about his son

But immigration officials have refused to green light their applicancy because their 13-year-old son, Nico, has Down syndrome.

"Our fight is more of a matter of principle," Montoya told CBC Radio's Metro Morning on Monday. "You have people who are deemed inadmissible because they may cost the state."

Montoya said when he first landed the job at York University, the international hiring officer warned him that he might encounter stumbling blocks to permanent residency because of Nico's condition, but he thought he must have misheard the officer.

"He was singled out solely because of his genetic identity," he explained. "The only difference is he has a genetic condition that makes him different."

Garcia-Prieto said it is "really, really devastating" for her to experience a process she believes to be unfair.

"Down syndrome people are victims of a stigma," she said. "It's just papers, they don't know the person."

'It's not fair'

This is not the first time Canada has barred entry or denied residency to people with illnesses or disabilities.

In 2011, a South Korean family living in New Brunswick faced deportation because their teenage son is autistic. The deportation order was later reversed amid public outcry.

Felipe Montoya, right, says his family was denied permanent residency in Canada because of potential health care costs associated with his son, Nico, who has Down syndrome. (Felipe Montoya/ Facebook) The National Post reported in 2012 that a University of Victoria professor from the U.S. and his family members were denied permanent residency in Canada because of their four-year-old son's autism.

The Immigration and Citizenship Act states "a foreign national is inadmissible on health grounds if their health condition might reasonably be expected to cause excessive demand on health or social services."

The couple said this is at odds with the Canadian Charter of Rights and Freedoms, which prohibits discrimination on the basis of disability.

Garcia-Prieto said friends and family back in Costa Rica cannot believe Canada would have such backwards rules.

"It's not fair," she said.

While Nico is too young to really understand what's happening, their 17-year-old daughter, Tanya, believes what's happening to her family is unjust, according to Garcia-Prieto.

All four family members will be moving back to Costa Rica in June, but Montoya plans to keep discussing the issue publicly.

He said he has already contacted his member of Parliament along with several cabinet ministers and added he won't stop fighting this battle until what he deems a discriminatory law is scrubbed from the books.