The proposed legislation appeared poised to pass the Senate but did not make it to a final vote before the summer recess began last week.
If Prime Minister Stephen Harper prorogues Parliament to deliver a new Speech from the Throne as expected in the fall, the bill will get rolled back to first-reading in the Senate again.
"The Senate should have passed this, and it's disappointing that the transgender community is going to have to wait months again now unnecessarily for them to do this, but I still expect them to pass the bill," said the bill's sponsor, New Democrat MP Randall Garrison.
Bill C-279 would protect transgender Canadians against discrimination in the Canadian Human Rights Act and prohibit the promotion of hatred or the incitement of genocide on the basis of gender identity in the Criminal Code.
This has been the fourth time the measure has come up as private member's business. In 2011, similar legislation got as far as third reading in the House of Commons but died on the order paper when the election was called.
This time it was passed in the Commons with the help of 18 Conservative MPs, including three ministers.
The bill was studied at the Senate's human rights committee this spring, and was reported back without amendment on June 11. But after that, it failed to be called up for a final, third-reading vote.
Complicating matters even more is an amendment to the bill proposed by Conservative Sen. Nancy Ruth. She complained that gender alone was not included in the Criminal Code section on hate, and she wants women to be specifically protected too.
Should Nancy Ruth's amendment pass, the bill would have to go back to the Commons for a vote on the altered version.
"I have no confidence that the members from the Conservative party who voted for it in its previous form would vote for it as amended," said Garrison.
Committee chairwoman Mobina Jaffer said she suspected the Conservative government wasn't in a hurry to have the bill pass.
"We had the belief that we had sufficient people to get the bill through, and that's why I believe that it didn't come for a vote," said Jaffer.
"The testimony that we heard from the trans people was just heartbreaking, and when I left that committee I felt, this is not the kind of Canada we want. This bill was just the right thing to do."
But Garrison said he's never had any indication the prime minister's office had a particular view on the matter. He said the failure to reach a vote in the Senate seemed more a matter of that chamber's haphazard scheduling.
The office of government Senate leader Marjory LeBreton, who announced her resignation from the post Thursday, did not respond to a request for comment.
In the Senate and in the Commons, some Conservatives criticized the bill as opening the door to abuse by sexual predators. The critics, some of whom dubbed the legislation the "bathroom bill," suggested that pedophiles could gain protection by claiming they were lurking in bathrooms because they were transgendered.
"This bill will allow perverts to take advantage of the law, which is a problem I have," Conservative Sen. Don Plett said last month.
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