MONTREAL -- A Montreal-born woman involved in the legal challenge against Quebec's Bill 62 says she lives in constant fear when she leaves home wearing her niqab.

'I am always scared because I don't know what will happen when I go out," Marie-Michelle Lacoste told a news conference Tuesday.

Lacoste, who converted to Islam in 2003, filed the challenge in Quebec Superior Court on Tuesday along with the National Council of Canadian Muslims and the Canadian Civil Liberties Association.

The recently adopted Bill 62 prohibits students from covering their face in class.

It also forces people whose fare requires a card with photo ID to uncover their face before riding public transit, although they can put the veil back on once they've been identified.

Court documents say Lacoste began wearing the face veil in 2011 "out of a sincerely held belief that this was an appropriate and authentic expression of her religious convictions."

Lacoste said she is worried about how Quebecers will react to the law, adding she was already being bullied, insulted and threatened before it passed.

"The message the government sends to the citizens is that if they already have negative thoughts about Muslim women wearing the niqab, the law tells them it's OK to think this way, (that) you are right to harass them, to threaten them, to insult them," said Lacoste, who uses the name Warda Naili.

The court challenge states that the face-veil law "gravely infringes" the religious and equality rights of certain Muslim women in the province.

The court challenge takes direct aim at the section of the law that forces public sector employees and private citizens to have their face uncovered when giving or receiving public services.

"This requirement directly infringes the freedom of religion of individuals, such as Muslim women, who cover their faces as a religious practice," it said.

Ihsaan Gardee, executive-director of the National Council of Canadian Muslims, told the news conference the law is clearly aimed at Muslim women who wear a face veil.

"Our legal challenge targets the heart of what this law really is: a discriminatory, unconstitutional and unnecessary piece of legislation that excludes and stigmatizes an already marginalized and vulnerable minority of women and, by extension, the larger Quebec Muslim community," he said.

In Quebec City, Premier Philippe Couillard briefly commented on the challenge, saying, "we deliberately wrote a bill that respects the charters and we're very comfortable with that."

Justice Minister Stephanie Vallee, who spearheaded the legislation, said much the same thing.

"It is a law that is respectful of the rights and freedoms that are guaranteed by the charters," she said.

Vallee has previously said the face-veil ban was instituted in order to ensure proper communication, identification and security during the exchange of public services.

The law has been panned across the country by federal and provincial politicians, who see it as targeting a small minority of Muslim women -- essentially the only citizens who regularly wear face veils in public.

Vallee has said the legislation doesn't target any religious group and says most Quebecers agree with the principle behind the bill.

Montrealer Fatima Ahmad, who has been wearing a niqab since she was given it as a gift more than a year ago, says in an affidavit included in the court document that her life has become significantly more difficult since Bill 62 became law.

Ahmad, 21, said she is concerned it will affect her ability to continue going to university, visit the library, see the doctor and take public transit.

The second-year McGill University student now avoids taking public transit for fear of being turned away or being asked to remove her niqab.

In an interview Tuesday, Ahmad said she's also had to deal with various comments ever since she began wearing it and has faced 20 or 30 incidents over the past year.

"I wasn't too concerned because I felt it was normal that people would not be familiar with what I wear so I was expecting it a bit," she told The Canadian Press.

"A lot of people threatened me, somebody also tried to take my niqab off (and) most people just curse at me from a distance.

"They tell me many things like: 'This is Canada, go back to your country, learn how to dress properly. This is not Halloween.'"

A judge is expected to hear a request next Wednesday for the law to be suspended temporarily.