Women in Ontario "lose their jobs for objecting to dress codes all the time," says one legal expert who helps employees in these situations, but there are ways for them to fight back against this kind of discrimination and protect themselves and their jobs.

CBC Marketplace investigated the dress codes at some of Canada's top restaurant chains and heard from dozens of female staff who say they felt pressured to wear revealing outfits or risk losing shifts.

The dress codes, which can call for women to wear high heels, tight skirts and heavy makeup, may in fact violate their human rights and they have every right to object, says Kathy Laird, executive director at the Human Rights Legal Support Centre.

"I encourage women to call us because there's no doubt that women do lose their jobs for objecting to dress codes all the time," Laird told CBC News. "So a woman has to assess how safe her job is in the circumstances if she starts raising trouble."

The centre offers free legal help to women who wish to file a complaint directly to their employer or with the Human Rights Tribunal of Ontario.

According to the Ontario Human Rights Commission, "employers can have a dress code or rules about dress that meet the business needs of the organization, as long as they comply with the [Human Rights] Code."

These rules have to apply to all employees.

"While it is acceptable for men and women to have different uniforms, employers must make sure that any uniform policy does not undermine the dignity and right to full participation in the workplace of employees of either sex. An employer should be prepared to prove that any sex-linked differences in the dress code are bona fide occupational requirements," the OHRC says on its website.

The uniform must not ask female employees to meet "more difficult requirements" than their male co-workers or expect them to dress "provocatively to attract clients."

"It is discrimination based on sex to require female employees to wear high heels, short skirts and tight tops," the OHRC says.

'Make sure that they're not alone'

The first thing a woman should do if she feels her job is threatened unless she dresses a certain way, Laird says, is speak to a trusted co-worker about the situation.

"Make sure that they're not alone and that the dress code that is objectionable is something that others are being asked to comply with, as well," Laird said. "That way you know the lay of the land."

Her next piece of advice is to take notes. If your employer is being critical while you're on the job or you're sent home because you're not wearing the exact clothing you've been told to wear, keep a record of these incidents.

"If her job is at risk, she should call us sooner rather than later," Laird says.

If a group of women gets together and writes a joint letter outlining their concerns, they should send it to their company's head office, she says.

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The more women who are willing to stand together, the stronger the position they will be in.

"The employer doesn't want to send an entire shift home," she said.

But if they are too afraid, lawyers can contact the employer on their behalf.

"If they do lose their job or suffer some workplace penalties like fewer shifts and that kind of thing, then we can protect them by contacting the employer and ultimately filing an application to the human rights tribunal," she said.

Laird said her office has not compiled statistics on the number of women who have had their jobs threatened over discriminatory dress codes. But she says her office gets "frequent" calls almost exclusively from women who work at bars and restaurants.

"We get calls on a regular basis," she said.

If you're experiencing dress code-related discrimination in the workplace, contact the Human Rights Tribunal of Ontario, or the Human Rights Legal Support Centre.