Branded "one of the gravest miscarriages of justice of recent years" by his solicitor, the Criminal Cases Review Commission (CCRC) on Wednesday announced it has referred Barry George's case to the Court of Appeal after a "thorough and intensive review".

The decision is based on new evidence which questions firearms discharge evidence used by the prosecution in George's original Old Bailey trial, and the significance attached to it. The evidence refers to a speck of firearms residue found in George's coat pocket.

George's solicitor Jeremy Moore said on Wednesday both he and his client were "very pleased" by the decision and commended the commission's "extremely thorough and careful approach" to the case.

Mr Moore said: "We are in the process of considering the lengthy statement of reasons prepared by the commission and thereafter will take stock and begin to prepare thoroughly for the forthcoming proceedings in the Court of Appeal where we hope to finally persuade the court that the verdict in this case was clearly unsafe.

"Mr George has now spent seven extremely difficult years in custody for a conviction which we believe that, in the fullness of time, will be seen as one of the gravest miscarriages of justice of recent years."

Mr Moore said he hoped to speak to George later on Wednesday, but understood he was "delighted" with the news. He said: "Today is I'm sure a relief but obviously there's still another hurdle to get over. But obviously he'll be very pleased to get to this stage."

Commenting on the basis of the referral, Mr Moore added: "It's certainly a matter that goes to the core of the case that the prosecution presented against Mr George."

Miss Dando was shot on her front doorstep on April 26 1999. George was convicted of the murder in July 2001 and sentenced to life imprisonment. The Court of Appeal dismissed his first appeal against conviction in July 2002. Lawyers acting for George then launched a new bid to clear him later that year.

CCRC chairman Professor Graham Zellick said the commission had "meticulously considered" every argument put forward on George's behalf. He said thousands of pages of documentation had been read, more than 100 people contacted or interviewed, expert advice and appraisals sought and extensive research examined. A committee of three commissioners had then "deliberated on every point" of the complex investigation, he added.