It might seem hard to imagine, but the legal profession has a long tradition of representing poor people without payment. In Ontario, however, that 700-year-old global custom could soon change.

In a 3-0 decision that redefines the concept of pro bono legal services, the Ontario Court of Appeal says lawyers who represent clients for free and emerge victorious can seek a costs award from the losing party.

It's not inappropriate or at odds with "the charitable purpose of volunteerism" for lawyers who have agreed to act pro bono in private legal disputes to receive some reimbursement for their services, said Justice Kathryn Feldman, who wrote Wednesday's decision on behalf of the court.

"It promotes access to justice by enabling and encouraging more lawyers to volunteer to work pro bono in deserving cases," she said.

The court awarded $4,500 in costs to lawyers who represented franchise owner Giuseppe Cavalieri on a pro bono basis in litigation involving two numbered companies.

Under the "loser-pay" costs system - in place in Canada and many common-law countries - the losing party in a civil action is usually required to pay some of the winner's legal costs. Today, full reimbursement is rare.

The original theory was that litigants should not be out of pocket for vindicating their legal rights or defending themselves against a meritless case.

Now, however, costs awards are also seen as a form of sanction. Some judges think the prospect of being ordered to pay an opponent's legal costs can help prevent abuses, such as frivolous lawsuits, and encourage settlements.

Allowing costs awards in pro bono cases offers another benefit, in addition promoting access to justice, Feldman said.

It ensures both sides know "they are not free to abuse the system without fear of the sanction of an award of costs."

Although there have been a handful of recent court decisions awarding costs to lawyers acting pro bono, this is the first time Ontario's highest court has offered guidance for judges across the province, said Jeff Leon, a lawyer representing the Advocates' Society.

"This is the first case where the Court of Appeal has taken a broad policy view," he said.

The court said a decision on whether to award costs to a pro bono lawyer is to be made on a case-by-case basis.

But before ruling on costs in any case, judges must now consider the implications for access to justice, it said.

"The case is significant because the court is recognizing that access to justice is an important consideration in awarding costs," said lawyer Paul Schabas, president of Pro Bono Law Ontario, an agency set up in 2002 to promote a "pro bono culture" in the legal profession.

Schabas said there isn't necessarily going to be "a run of cases" involving lawyers trying to recover some of the fees they sacrificed by working for free.

But the possibility of receiving costs is "a factor that will help increase the number of lawyers doing pro bono work," Leon said.

When Cavalier's case got to the Court of Appeal last year, he succeeded in getting several earlier, unfavourable court rulings overturned.

After he won, his lawyer, who was volunteering through a pro bono program run by the Advocates' Society, asked for costs, setting the stage for a debate over whether lawyers working for free can be paid.

Joseph Dallal, a lawyer representing the companies, argued that a costs award would be wrong because lawyers who agree to act pro bono are fulfilling a professional obligation and have no expectation of payment.

When costs are awarded, the money belongs to the litigant, although pro bono lawyers are free to make fee arrangements with their clients that allow the costs to be paid to the lawyer, the court said Wednesday.

"It's always open for a lawyer who doesn't want costs to donate them to charity, or to Pro Bono Law Ontario," Leon said.