A law association that defends the wrongfully convicted will help a Kingston, Ont., woman fight for the right to sue the expert witness who helped put her in jail for two years, charged with murdering her own child.

On Friday, the Association in Defence of the Wrongfully Convicted was granted the right to support Louise Reynolds's petition to sue forensic pathologist Dr. Charles Smith.

Smith, who bolstered murder charges against Reynolds by saying her seven-year-old daughter was brutally stabbed before her 1997 death, is protected from lawsuits by immunity granted to expert witnesses.

Prosecutors dropped the case against Reynolds in 2001, after other experts said that the child had likely been mauled to death by a pit bull.

The Ontario Court of Appeal will hear Reynolds's challenge to the immunity principle on Feb. 12.

Association in Defence of the Wrongfully Convicted member Cindy Wasser said the outcome will have important implications.

"This case will determine the issue of experts' accountability for the negligent work they've performed before they enter the courtroom," said Wasser, who is on the association's board of directors.

But Erik Knutsen, a civil law professor at Queen's University, said the immunity exists for an important reason, and it may be difficult to find witnesses to testify in court if they have reason to fear being sued.

"We don't want to make it impossible to get important people in a case to give evidence."

Seven-year-old Sharon was found dead in the basement of Reynolds's home in 1997.

Smith, who was head of the pediatric forensic unit at Toronto's Hospital for Sick Children, performed an autopsy on the child's body and concluded she had been stabbed more than 80 times.

That led to a charge of second-degree murder against Reynolds, who spent two years in jail awaiting trial.

A second autopsy by other medical experts confirmed Reynolds's claim that the girl had been mauled to death by a pit bull.

In March 2005, Ontario's chief coroner, Barry McLellan, called a review into 44 child death cases in which Smith performed autopsies or offered expert opinions. The review, called after tissue samples in child homicide autopsies went missing at the Hospital for Sick Children, is ongoing and results are expected to be released in the spring.