A B.C. woman who escorted her ill 89-year-old mother on a trip to end her life in Switzerland last year is challenging the law that makes the same act a criminal offence in Canada.

Lee Carter and her husband filed a suit in B.C. Supreme Court Tuesday seeking to allow mentally competent adults suffering from incurable serious illness the right to physician-assisted suicide.

Carter said her mother, Kathleen Carter, suffered from spinal stenosis, a degenerative condition that left her in a wheelchair and caused her chronic pain.

"While the disease would never kill her, it would leave her paralyzed," Carter said. "When it got to the point that she could not move herself, could not [feed] herself, incontinent and totally dependent on others … she realized she wanted to die … and to die with dignity."

Her suit argues the laws against obtaining medical help to assist suicide are unconstitutional because they deny individuals control over their physical, emotional and psychological dignity.

Legal in some states

Under Canadian law, it's illegal to counsel, aid or abet a person to commit suicide, and anyone convicted of the offence could be imprisoned for up to 14 years.

Assisting suicide is legal in Oregon and Washington states as well as in Switzerland, Belgium, Luxembourg and the Netherlands.

The B.C. Civil Liberties Association and a Victoria-based family doctor are also plaintiffs in the suit.

The Supreme Court of Canada ruled against B.C.'s Sue Rodriguez in a similar case in 1993.

Rodriguez suffered from amyotrophic lateral sclerosis, also known as Lou Gehrig's disease, and wanted to overturn the law.

Although the court at the time upheld the Criminal Code, the issue should be revisited, said Grace Pastine of the BCCLA.

"We believe the time has come to bring that issue back before the court," said Pastine. "And we believe that this time, the court will decide differently."

With files from the CBC's Terry Donnelly and Belle Puri, and The Canadian Press