Ms Dando, 37, was shot dead outside her home in Fulham, west London, on 26 April 199
The family of a man who was wrongly convicted of the murder of Jill Dando said they have no faith that the Metropolitan Police “will fully and properly investigate” claims she was killed in error by a Russian hitman.
It comes after court papers reportedly suggested that French fashion boss Gerald Marie hired a killer to “deal with” BBC journalist Lisa Brinkworth after she went undercover to expose his agency Elite Model Management.
They claim that Ms Dando may have been shot dead on her doorstep by mistake due to a confusion of identity because of similarities in the appearance, occupation and addresses of the two women.
Crimewatch presenter Ms Dando, 37, was shot dead outside her home in Fulham, west London, on 26 April 1999.
Barry George endured an eight-year-long prison sentence after being wrongfully convicted of killing her. In August 2008, Mr George was acquitted of the crime at retrial.
He was the only person ever to be put on trial for Ms Dando’s murder.
In light of new developments regarding the alleged confusion of a Russian hitman, Michelle Diskin Bates, Mr George’s sister, told The Mirror: “If this can be proved then it is huge.
“But that’s going to leave the Dando family, who were always told by police they had the right person, to realise how badly they were let down.
“There are two families in the middle of a turmoil. If this is true, how could police have got it so badly wrong? We’ve had to live with this every single day.”
She continued: “We never believed police believed he was guilty, we know serving officers that don’t believe he did it.
“We need to see this story play out. Barry will not be ‘free’ unless they have 100% proof somebody else did it.
“Do I have faith they will fully and properly investigate this latest story? No I don’t, not at all.”
Mr Marie, 72, is being investigated in France over multiple accusations of alleged sexual assaults, all of which he denies.
Ms Brinkworth alleges she was assaulted by Mr Marie in 1998 while working undercover on a BBC exposé about sex crimes in the fashion industry.
Lawyers in the documents submitted to a court in Paris refer to a conversation witnessed by former Elite executive Omar Harfouch in which Mr Marie allegedly ordered a member of the Russian mafia to “deal with a problem”, the Daily Mail reports.
The papers from French law firm Bourdon Associes reportedly state: “Shortly thereafter… a BBC journalist, Jill Dando, was shot dead in April 1999.
“Indeed, these two journalists were in their thirties, were blonde with the same facial features, of the same height and of similar stature.
“They lived close to each other and had people in common, including the husband of Jill Dando.”
A spokesperson for the Metropolitan Police said: “The investigation into the murder of Ms Dando remains open, as with all murder investigations.
“We will always explore any new information which may become available.”