HAMILTON, Canada — Transgender people are effectively barred from flying on Canadian flights due to an obscure rule change that came to light last week.

Queer community and transgender blogs blew up with news that under the obscure identity screening regulations for air passengers in Canada, travelers whose gender identity on their identification doesn't match their person will not be allowed to board a Canadian airline.

“We cannot allow regs which judge people based on how they 'appear' to be gendered; it is unacceptable,” wrote Christin Milloy, a trans activist on her blog. Milloy led the early outrage online over the regulations. An online petition has since been started calling for a repeal of the exclusion.

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The rule change apparently happened in July 2011, shortly after the federal election in Canada, but went unnoticed until recently by the trans community.

Milloy suggests that the requirement may have flown under the radar because it didn't require a vote of Parliament or public consultation process, but was part of a suite of changes to air security regulations Canada has been putting in place since 9/11 — as a kind-of Canadian version of the "no-fly" list in the US.

So far there hasn’t been a report of any instance where a transgender person has been prevented from boarding a Canadian flight. But it’s raised concerns about harassment or discrimination in the transgender community, which already has been pushing for increased protection under the law.

Proposed changes to the Canadian Human Rights Code that would have enshrined transgender rights passed in the Canadian Parliament, but died in the Senate just before the last election and have yet to be resurrected.

Now in the wake of the flight ban controversy, the NDP, the official opposition party in the federal parliament, is once again seeking protections for transgendered Canadians in the Human Rights Code, with the introduction of Private Members Bill C-279.

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"Air Canada does not set these rules,” said Peter Fitzpatrick, an Air Canada spokesman. “They are regulations from Transport Canada, and we must enforce them.”

Transportation Minister Denis Lebel, the government minister responsible for air travel, said during Question Period in the Canadian Parliament last Thursday that his priority was “safety” of passengers on planes. A written statement from a ministry states that air screeners have to be able to identify travelers, “regardless of their culture, religion or sexual orientation.”

A motion to repeal the specific section of the screening regulations involving gender identity, brought forward by Opposition Member of Parliament Olivia Chow, was defeated 6 to 5 in a vote that split down party lines on Wednesday.

The only way to change the gender on a current Canadian passport is by proving that reassignment surgery has or will take place within one year. Trans community commentators say that the restriction effectively grounds the majority of transgendered people who are non-operative, or who simply gender-identify as other than their birth gender. That, they say, amounts to discrimination.

Under Canadian health coverage laws, a person has to live for at least one year in their assumed gender identity before being considered for reassignment surgery.

Some trans reaction online was more understanding of the Canadian government’s intent with the regulations on the basis of air security, citing how changes also banned passport holders and airline passengers from wearing a burka, hijab or other head covering that obscures their identity.

Opposition parliamentarian Randall Garrison, who has been an outspoken advocate for LGBT issues, is calling for a repeal of the specific gender-identity exclusions in the passenger screening regulations, but the government hasn’t signalled that any change to the regulations is forthcoming.

Blogger-activist Milloy tested the ban earlier this week, but was not stopped on a flight from Toronto to Newark, tweeting that the airport security screener recognized her from TV.