Canada's top court has shut down a bid from a B.C. man trying to challenge the so-called "bubble zone" law that protects the area surrounding abortion clinics.

Donald David Spratt says the zone violates his freedom of expression and was hoping to convince the Supreme Court of Canada the law restricting protests in front of abortion clinics is unconstitutional.

But the court dismissed his claim without giving a reason.

The decision upholds the Access to Abortion Services Act, which makes it illegal to interfere with a doctor or patient within 50 metres of an abortion clinic.

Spratt was convicted in 1998 after standing in front of a Vancouver clinic with a large wooden cross that read "You shall not murder."

He spoke to workers as they came out of the clinic about the value of the love of God and the necessity of redemption from sin.

Precedent

Last September, the B.C. Court of Appeal shut down shut a decade long battle by Spratt and Gordon Watson, another anti-abortion activist, by upholding the bubble zone law.

The unanimous decision agreed the right to oppose abortion is constitutionally protected, but said limits on that expression are justified in order to protect vulnerable women accessing health care services.

Jill Doctoroff, director of the non-profit Elizabeth Bagshaw Women's Clinic, said the decision is consistent with Canadian law.

"This is a legal and medical procedure in an accredited medical facility," Doctoroff said.

"We're pleased women are able to access service without harassment and staff and nurses and physicians can go to their workplace without being harassed for what they do."

With files from The Canadian Press