A lawsuit has been filed on behalf of a B.C. family who travelled to Switzerland last year to help an aging family member end her life, because laws in Canada would have made the act illegal.

The lawsuit alleges that laws that prohibit assisted suicide deny people the right to make choices about their own physical and emotional dignity.

The B.C. Civil Liberties Association filed the suit in B.C. Supreme Court Tuesday in an attempt to reverse the current laws banning doctor-assisted suicide.

The BCCLA wants to see changes to the Criminal Code that would allow mentally competent adults with incurable diseases the right to seek medical help to end their lives.

"We want every Canadian to have a choice to have what they consider to be a good death," Grace Pastine, litigation director for the BCCLA, told reporters at a Vancouver press conference.

"Inflicting unbearable suffering on individuals, on dying patients who wish to end their lives, is unjust, unacceptable and unconstitutional."

The lawsuit was filed on behalf of Lee Carter and her husband Hollis Johnson, of Fort Langley, B.C. They travelled with Carter's 89-year-old mother, Kay, to Switzerland last year to help her end her life.

Before she left, Kay Carter told CTV News why she was making her decision. She said she suffered from spinal stenosis, which left her in chronic pain and almost immobile. She could do little for herself, was confined to a bed, or wheelchair and was losing her sight and hearing.

"As far as I can see it, there is absolutely no quality of life in this at all," she told CTV in September, 2009.

So in January, 2010, she travelled to Switzerland, where assisted suicide and euthanasia are legal, and sought the help of an assisted suicide group called Dignitas.

She died from a lethal dose of sodium pentobarbital on Jan. 15, 2010 after writing a farewell letter to friends.

Now Carter and Johnson are moving ahead with this legal challenge in hopes that it will allow mentally competent adults the right to medical assistance to hasten death.

They plan to argue that Criminal Code provisions against physician assisted-dying are unconstitutional because they deny individuals the right to have control over choices that are fundamental to their physical, emotional and psychological dignity.

"My mother, Kay, was a lifelong supporter of the dying with dignity movement. She lived her life with passion, independence and resolve, and her independence extended to insisting that she would have choice and control over how she would leave this world," Lee Carter said in a release.

"I feel that I'm honouring her memory by participating in this legal challenge."

Victoria physician Dr. William Soichet is also named as a plaintiff in the suit. He treats patients suffering from diseases like cancer, Huntington's disease and multiple sclerosis, and says he would be willing to help patients end their lives.

"Dr. Soichet considers the ability to participate in physician-assisted dying on request, in appropriate circumstances and where there are all the necessary safeguards in place, an important component of the provision of health care to grievously and irremediably ill patients," the lawsuit reads.

The Attorney General of Canada will have 21 days after being served with the claim to file a response.

The BCCLA's claim is one of two right-to-die suits filed this month in B.C. Supreme Court. The Farewell Foundation for the Right to Die filed a claim on Apr. 8, also contesting the laws against assisted suicide.