The Supreme Court of Canada is hearing a case of alleged sex discrimination that could have powerful repercussions across the country.

In 1994, Tawney Meiorin, an experienced "smoke jumper," or forest fire fighter, was dismissed from her job after failing a fitness test. She had to run 2.5 kilometres, and took 49 seconds longer than required.

The Supreme Court will decide whether the fitness test discriminates against women.

When Meiorin was dismissed, her union took the case to a labour arbitration board, which ordered her reinstatement. The B.C. government, however, took the case to the B.C. Court of Appeals, which ruled that fitness tests were not discriminatory.

Meiorin was dismissed again, and took her case to the Supreme Court.

The B.C. government says the fitness tests are necessary. The tests were imposed in the early 1990s after the death of a fire fighter. According to the government, there have been fewer injuries since the introduction of the tests, and lowering the standards for women would increase risks.

"Lowering the standard for women, or any other protected group such as the disabled or older persons, is simply not a reasonable option because it would create an unsafe situation," government lawyers say.

Supporters of Meiorin say the test is unfair because women naturally have a lower aerobic capacity then men.

The case could decide the legality of such fitness tests, which are mandatory in several professions across Canada.