Jason Kenney took to Twitter on Friday to publicly promote his directives while immigration minister to forbid Muslim women from wearing niqabs while taking the oath of citizenship.

"I believe people taking the public oath of citizenship should do so publicly, w/ their faces uncovered," Kenney, who's now employment and social development minister, Tweeted amid an ongoing lawsuit over the ban against the federal government.

He asked his 35,700 Twitter followers if they agreed with his stance.

Zunera Ishaq, a Pakistani woman now living in Mississauga, is suing the Conservatives, arguing the ban violates her Charter rights by failing to accommodate her religious beliefs.

Niqabs are worn by some Muslim women in public areas and in front of adult males who are not relatives.

Policy change 'unauthorized', says lawyer

In a Federal Court hearing Thursday in Toronto, one of her lawyers accused Kenney of imposing his own ideology on citizenship ceremonies when he imposed the ban unilaterally in late 2011 in an operational manual.

At the time, Kenney said the niqab represented a view of women that is unacceptable in Canada.

Lorne Waldman, a co-counsel for Ishaq, scoffed at Kenney's public defence, pointing out that the Citizenship Act does not require people to be seen or heard taking the oath.

"Jason Kenney can believe in anything he wants as a private citizen, " he said in an interview on Friday.

"But the minister is confusing his personal beliefs with his obligations as a minister of the Crown. As a minister of the Crown, he has to uphold the laws, and not only was the policy change he made unauthorized, it's inconsistent with existing laws and with the Charter."

He added it was "unusual" for Kenney to weigh on a matter before the courts.

"One would expect at this point for the minister to wait for the court process to unfold," he said.

Citizenship a privilege, government says

The government lawyer arguing the case said becoming a citizen is a privilege, not a right, and pointed out that Ishaq had removed her veil to get a driver's licence.

Negar Hashemi also said Ishaq declined an offer to take the oath at the front or the back of the citizenship court.

Ishaq, who was sponsored to come to Canada from Pakistan by her husband, put the brakes to her citizenship ceremony in January when she learned of the veil ban.

Her lawsuit could result in the policy being scrapped.

The judge has reserved his decision.

In a speech on the policy change three years ago, Kenney said he was responding to concerns about those taking the oath while their faces were concealed.

Complaints from MPs, citizenship judges cited

"I have received complaints from members of Parliament, from citizens, from judges of the citizenship court that it is hard to ensure that individuals whose faces are covered are actually reciting the oath," he said.

"Requiring that all candidates show their faces while reciting the oath allows judges and everyone present to share in the ceremony, to ensure that all citizenship candidates are in fact, reciting the oath as required by our law."

He added that "to segregate one group of Canadians or allow them to hide their faces, to hide their identity from us precisely when they are joining our community is contrary to Canada's proud commitment to openness and to social cohesion."

A month after he announced the ban, Kenney said polling had shown eight out of 10 respondents agreed with the ban.

The Muslim Canadian Congress also honoured his "courageous decision," saying niqabs and burkas are used as political tools by Islamists who seek to segregate Muslims into religious ghettos and cut them off from mainstream society.

Storify by CBC News