The Supreme Court of Canada has reserved judgment in a case involving a teenager who is seeking to overturn a law that forced her to have a blood transfusion against her will in 2006.

Lawyers for the teenager, who is a Jehovah's Witness, argued that the Manitoba government violated the girl's constitutional rights when it used legislation that says minors must be at least 16 years old to make medical decisions.

The teen, now 16, was 14 years old and living in Winnipeg when doctors gave her a blood transfusion to treat a flare-up of her Crohn's disease. She wanted to be treated without the transfusion.

Most Jehovah's Witnesses interpret literally a passage in the Bible that forbids them from ingesting blood — which includes receiving blood transfusions — although some blood derivatives are allowed.

Despite her wishes, Manitoba Child and Family Services obtained a court order compelling her to have the procedure after it was recommended by her doctor.

Her lawyers argued before the top court that the Manitoba child welfare law should be overturned and that there should not be a set age at which decisions about a young patient's medical wishes are made differently.

Instead, the decisions should be made on a case-by-case basis, according to the intellectual capability of the person involved, they argued.

The case could have far-reaching implications because several other provinces have laws setting 16 as a legal benchmark in such cases, and some set the cut-off point as high as 19.

With files from the Canadian Press