The attorney general's submission to the country's top court comes as the Harper government moves to further tighten voting restrictions under its controversial Fair Elections Act.
The legislation — also known as Bill C-23 — marks the second time the Conservatives have moved on what they perceive to be an issue of voter fraud, and it comes while their first round of reforms is still being legally contested.
Three British Columbia voters, with the help of the B.C. Civil Liberties Association, are seeking leave to appeal to the Supreme Court their constitutional challenge of the 2007 voter ID reforms.
The court has not yet decided whether it will hear the appeal.
Two lower courts found the identification reforms did constitute a Charter breach, but ruled the breach was justifiable because the rules were "minimally impairing."
Federal lawyers say the top court should not revisit the case because it does not raise a matter of public importance.
The government argues the 2007 reforms "serve to make the rare events of fraud and error rarer, which protects the integrity of the vote and maintains public confidence in the electoral system."
That's not the case that has been put to the Canadian public by Pierre Poilievre, the Conservative minister for democratic reform.
Since introducing Bill C-23 at the beginning of February, Poilievre has repeatedly raised the alarm over voter fraud to justify the elimination of "vouching" for people without proper ID.
Under the 2007 law, a fully documented voter can vouch for the identity of a voter without full ID.
"The risks of vouching are obvious," Poilievre told the Commons on March 24 as he championed a further tightening of the rules.
"It is obviously risky to allow someone to vote without having any documented ID of who they are or where they live."
Poilievre then cited a report commissioned by Elections Canada to say vouching safeguards "were violated 50,735 times, or 42 per cent of the time, in the last election."
Yet government lawyers have been arguing in B.C. courts since 2009 that vouching is a "failsafe" that protects the constitutionality of the 2007 voter ID rules — a position the government continues to maintain in its current submission to the Supreme Court.
The federal brief lists three ways voting rights are protected under the 2007 law — the third being vouching — and says the system works.
"The identification system itself — in providing three possible (voting) options and in authorizing a broad number of documents — is specifically designed to be accessible and least intrusive for all voters, while still being capable of meeting Parliament's integrity objectives effectively," says the attorney general.
Last month, the Conservatives announced a number of amendments to Bill C-23, including a partial climbdown on the vouching ban. The bill would now permit a fully documented voter to sign an oath attesting to the local residency of another voter, who must still be able to show personal ID.
"The Fair Elections Act will eliminate the use of vouching for identity purposes," Poilievre reiterated Monday in the House of Commons.
In seeking to have their case heard by the Supreme Court, the three B.C. voters cited the latest Conservative elections bill and argued the court could provide "guidance" to federal and provincial legislatures on constitutional issues around voter ID laws.
In the response to the appeal application, the attorney general argued that the top court should ignore the Fair Elections Act.
"It may never be enacted or may undergo amendment," says the federal brief.
"No question of public importance can be inferred from proposed legislation."
Prior to 2007, Canadians were not required to show ID when they voted in federal elections as long as their name appeared on the voters' list.
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