A bill to toughen mandatory-vaccination rules for schoolchildren looked to be in trouble on Wednesday as more MLAs spoke out against its use of the Constitution's notwithstanding clause to forestall legal challenges.

Three People's Alliance MLAs said they may not support the bill because of the inclusion of the clause, which leader Kris Austin called a "nuclear button" that should be used only rarely.

The bill introduced last week by Education Minister Dominic Cardy would eliminate religious and philosophical exemptions to the policy of forcing children attending public schools to be vaccinated.

Including the notwithstanding clause would allow the law to override 10 sections of the Charter of Rights and Freedoms, including those that guarantee freedom of religion.

"I think the inclusion of that is an admission that they're violating somebody's rights," Alliance MLA Rick DeSaulniers told reporters. "It's really quite simple. It's obvious."

Premier Blaine Higgs says suspending charter rights is necessary to get a critical mass of students vaccinated to protect public health. (CBC)

Premier Blaine Higgs confirmed DeSaulniers's analysis when he told reporters that government lawyers concluded the bill would violate charter rights and would be struck down if it didn't include the notwithstanding clause.

"It's something I would have preferred not to utilize," Higgs said, but the legal advice was "that we'd be challenged and ultimately lose" in court without the clause.

Higgs also revealed that the government consulted lawyers about filing a reference case to the New Brunswick Court of Appeal on the constitutionality of the bill.

But "the opinion was that the reference case would come back and say 'no, this is unconstitutional," he said. "You don't put legislation forward that you know is not respecting the law."

He said suspending charter rights in this case was necessary to get a critical mass of students vaccinated to protect public health.

"What's the greater good?" he said.

Higgs will allow all PC MLAs, including cabinet ministers, to vote their consciences on the bill.

He said he'll vote for it. Cardy said he had "no idea" if the legislation will pass.

Not convinced of crisis

As more MLAs lined up against the bill, Cardy said those who say they support vaccinations should "sit down, either with me or by themselves, and figure out a way we can make this happen. If they're committed to protecting children, that's fantastic. Let's make it happen."

DeSaulniers, Austin and colleague Michelle Conroy all said they would listen carefully during the coming debate but so far they're not persuaded there's a vaccination crisis that requires the notwithstanding clause.

"I'm not convinced that's the case right now," Austin said. "We're kind of using the nuclear button here on an issue that I don't think warrants it."

Conroy said she is "on the fence" about how she'll vote but is concerned about suspending charter rights.

During hearings in August on an earlier version of the bill, MLAs were told that the government does not have a complete picture of vaccination rates among school children.

People’s Alliance Leader Kris Austin calls the inclusion of the notwithstanding clause a 'nuclear button' that should be used only rarely. (Jordan Gill/CBC)

The Progressive Conservative minority government has relied on the three Alliance MLAs for support to pass legislation, so the bill could be doomed if all three of them vote against it.

Cardy argues the bill is necessary to ensure a critical mass of students, which he puts at 95 percent, are vaccinated to create "herd immunity" that protects those who can't use vaccines for legitimate reasons.

Meanwhile, the opposition Liberals may be on the verge of abandoning their plan to allow a free vote on the bill, also because of the notwithstanding clause.

Clause goes too far for Liberals

Liberal Leader Kevin Vickers had promised a free vote on a previous version of the legislation. But MLA Rob McKee said all 19 of the party's MLAs could oppose the new version.

He said it goes too far in suspending charter rights before the government has come up with a clearer estimate of whether vaccination rates are below the 95-percent threshold.

"It would certainly be easier as a caucus to have that free vote if the clause was not there," McKee said. "We believe that that clause is going too far in these circumstances to infringe pre-emptively on the charter rights of individuals."

Both McKee and Green Party Leader David Coon said they will consider introducing an amendment to the bill to remove the notwithstanding clause.

Liberal MLA Rob McKee says the inclusion of the notwithstanding clause in the vaccine bill goes too far in suspending Charter rights. (CBC)

Coon called it "unconscionable" that the PC government would include it in any bill because it could lead to a slippery slope of the clause being used more often.

"It should never have been contemplated," he said.

Coon said he will vote for Cardy's bill if the clause is removed, though his Green colleague Megan Mitton suggested she would oppose it either way. She said public-health officials have argued there are better ways to encourage vaccinations than a mandatory law.

"I think this should be a last resort, but I fully support vaccination and I think there is a better way to do this," she said.

MLA calls Cardy 'Hitler-ish'

The legislation has provoked heated comments by MLAs since its introduction. Liberal MLA Cathy Rogers publicly apologized in the house Wednesday after describing Cardy in a Facebook comment as "Hitler-ish" for using the notwithstanding clause.

"I crossed the line. … I do deeply regret making the comment," she said.

On Tuesday, Cardy said some opposition MLAs had chosen "to ally themselves with" conspiracy theorists and anti-Semites on online anti-vaccination discussions.

McKee said Wednesday that if Cardy adopted a calmer, more civil tone it might lead to a more productive debate on the issue.

The minister responded that he's passionate about helping children and, contrary to other politicians who worry about losing votes, he prefers to be honest and direct about his views.