OTTAWA -- Former NDP leader Tom Mulcair said his successor Jagmeet Singh has "completely abandoned" Mulcair's legacy of defending religious rights in his handling of the debate over Quebec's secularism bill.

In 2015, Mulcair paid a political price in Quebec after he supported women's right to wear a niqab. Then-prime minister Stephen Harper was trying to ban the religious garment at citizenship ceremonies – an effort that was later ruled unlawful in a Federal Court decision.

In an interview with CTV's Power Play airing Thursday, host Don Martin asked Mulcair if he felt Singh has defended that legacy in his approach to Quebec's secularism bill, Bill 21.

"No no, he's completely abandoned it," said Mulcair.

"He says very clearly that Francois Legault is allowed to adopt Bill 21. He says that he personally has difficulty with something that he calls 'divisive,' but Francois Legault has restricted people's religious rights in the province of Quebec."

While Jagmeet Singh has said he is personally opposed to the bill and called it "saddening," he has also emphasized the importance of ensuring there is no political interference in the ongoing court challenge against it. That means a federal government led by Singh would not step in to fight the bill in court anytime soon.

Mulcair went on to say that Singh's stance on the law, which would prevent a practicing Sikh wearing a turban from becoming a police officer, was "a bit surprising."

"Mr. Singh earlier this week applauded the unanimous decision of Calgary City Council to come out and call, and say very tough things about Bill 21," added Mulcair.

Many leaders have been tip toeing around the issue, which has proven to be a thorny one among Quebec voters. The province has a strong tradition of fierce advocacy in favor of secularism – and has previously punished politicians who speak out against pushes for increased provincial secularism.

Most party leaders have said they will allow the courts to wrestle with the provincial legislation. However, Mulcair said that Liberal Leader Justin Trudeau moved the needle slightly on the issue during last night's French-language leaders’ debate.

"It's really playing into the media here in Quebec today because he left the door really open to an eventual court challenge by a federal government led by him," said Mulcair.

Trudeau won French-language debate: Mulcair

Mulcair also told Martin that he believes Trudeau emerged the champion of last night’s debate – and Conservative Leader Andrew Scheer had the toughest night.

"Mr. Trudeau won last night's debate because he didn't get knocked out. He's the champ, he walks into the ring, anybody else wants to beat him, they've got to knock him out,' said Mulcair.

"No knockout punches last night."

Mulcair said it was a "wonderful" debate, but Trudeau emerged "without a scratch." As for Scheer, he said the Conservative leader stumbled because he had the greatest difficulty dealing with a "totally predictable, tough issue, which was the abortion debate."

"Andrew Scheer somehow appeared unprepared for the question," said Mulcair. "The substance of his debate was well-prepared, but the one nettlesome issue that he's had trouble with for months now, they didn't have an answer."

Scheer has since clarified that he is anti-abortion, but would not allow the debate on the issue to be reopened.