The 38-year-old solicitor was freed by the Appeal Court after her conviction in 1999 for murdering her two baby sons was ruled "unsafe".

Two pathologists may face action from the General Medical Council after their evidence led to her conviction.

Mrs Clark's acquittal has also brought hope to another woman, Angela Cannings, who was also convicted of murdering two infant sons.

You must have experts from each side but, on the other hand, they must know they must always give all their facts to the other side, so everyone can look at all the evidence available Joshua Rozenberg Legal editor Daily Telegraph

Tests suggesting eight-week-old Harry Clark may have been suffering from a brain infection did not emerge until after the trial and first, unsuccessful appeal.

Mrs Clark's defence lawyer, Clare Montgomery QC, told the court that pathologist Dr Alan Williams withheld this information from the court.

Mike Mackey, Mrs Clark's solicitor, told GMTV: "The situation is that in some cases expert evidence is vital and there is an understanding between experts that come together to assist the court.

"In this case Dr Williams took the view that the finding of bacteria was not relevant.

Sally Clark Case Timeline

Dec 1996 11-week-old Christopher dies Jan 1998 Eight-week-old Harry dies Nov 1999 Sally Clark jailed Oct 2000 Court of Appeal: "overwhelming" case against her Jan 2003 Freed after new appeal

Crucial evidence that set Clark free

Joshua Rozenberg. legal editor of the Daily Telegraph, told BBC Breakfast expert evidence was given special privilege in English law because experts can give opinions, while other witnesses cannot.

He ruled out the use of a court-appointed expert because that would deprive defendants of the opportunity to call their own evidence.

"But their own experts will only be able to rely on the scientific tests done by the pathologist, who inevitably acts for the police and the prosecution," he said.

"You must have experts from each side but, on the other hand, they must know they must always give all their facts to the other side, so everyone can look at all the evidence available."

Fresh hope

Dr Williams initially said Harry had died from being shaken and then at the trial changed his finding to smothering.

He knew about Harry's infection since February 1998 but "he had kept the results secret from Sally Clark and her advisers", the appeal court was told.

Michael Green, professor of forensic pathology at Sheffield University, who has since retired, also changed his opinion about the cause of death.

A GMC spokeswoman said: "We are aware of the doctors and are considering whether action, if any, needs to be taken."

Today is not a victory. We are not victorious. There are no winners here. Sally Clark

Sally Clark's statement in full

The husband of a mother jailed for life for murdering her two infant sons said today he hoped Sally Clark's successful appeal would lead to a review of his wife's case.

Terry Cannings, husband of Angela, has been fighting to clear his wife's name since she was convicted at Winchester Crown Court in April last year.

"Over the last three months I've put the two (cases) very much together and I do now hope that this will help Angela," Mr Cannings told BBC Radio 4's Today programme.

John Batt, Mrs Clark's solicitor, said there were similarities between the two cases.