Over the past several years, the Harper government has made some tough decisions on the immigration file: They've cancelled the immigrant investor program; they've tightened rules surrounding parents and grandparents immigration; they've rejigged the Citizenship Act; and they've tackled marriage and refugee fraud.

The next controversial issue on Immigration Minister Chris Alexander's desk is likely going to be 'citizenship by birth.'

Canada and the United States are the only two western countries that still automatically grant citizenship to anyone born on their soil. That means if non-citizens or non-residents have their baby in Canada, the baby becomes a citizen and can, as an adult, sponsor his or her parent for immigration.

According to a 'secret' 2013 document presented to then-immigration minister Jason Kenney — put together by various federal departments — the Harper government is being urged to eliminate that birthright.

The 17-page document was obtained by the Toronto Star via an access to information request.

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One of the main concerns is that automatically giving citizenship to those born in Canada can lead to fraud.

In 2013, the National Post reported on a CBSA document which suggested that a number of pregnant Nigerian women made their way to Canada in a "pattern... reminiscent of an attempt to exploit birthright laws."

The Post called it "birth tourism."

Foreign-language websites now offer to house pregnant mothers close to hospitals in the “maple syrup kingdom,” while listing the social welfare benefits available in Canada — free education, free health care, child benefits, old age pension. Many of the websites offer toll free calling from China. “The best gift you can give your newborn is a Canadian passport,” reads one such website, which rates Canada favorably against the U.S. since the latter offers relatively poor welfare benefits and the costs of living and education are higher.

A government source confirmed to Yahoo Canada News that they are indeed "reviewing citizenship policy with regard to the issue of birth tourism" but that no final decision has been made.

Any change to the existing policy would require co-ordination with the provinces as they are ultimately responsible for issuing birth certificates.

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Critics, however, are urging the government to proceed with caution.

Some worry that the policy is too harsh and could, at some point, deem certain individuals born in Canada stateless.

"This proposal is in line with the governments ideological approach to immigration rather than any evidence-based solutions," immigration attorney Michael Nirentold Yahoo Canada News.

"The government wants to block as many roads to Canadian citizenship as it can. Contrary to the trend of globalization, we are taking a more isolationist stance when it comes to immigration and citizenship. This is the opposite approach of what Canada needs given it's aging demographic.

"These cases represent such a small minority of the total births per year that one can only conclude it's the government's ideology of isolation that is driving policy."

Andrew Griffith, formerly a director general for citizenship and multiculturalism at Citizenship and Immigration Canada, says that the small number of children born to foreign nationals doesn't necessarily justify the cost to annul the law.

"There is no evidence that this is a major problem," Andrew Griffith, formerly a director general for citizenship and multiculturalism at Citizenship and Immigration Canada, told Yahoo in an email exchange.

"Possibly 500 cases out of annual births of some 360,000."

According to the secret report — referenced above — if the federal government was to nix the birthright, there would be significant costs to bear with regard changes to the way provinces register births, a new national system to prove citizenship and enforcement infrastructure.

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For their part, the opposition parties seem undecided on the issue.

The NDP didn't respond to an email request from Yahoo Canada News asking for their views.

Meanwhile, Liberal immigration critic John McCallum told Yahoo that while he's always "suspicious" of the Conservatives on immigration reform, they don't have a position as of yet.

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