Maria Dingwall, the daughter of Bentley's sister, Iris, who died last January, has been campaigning for a pardon for her uncle and for his case to be referred to the Court of Appeal. She is vehemently opposed to capital punishment.
She was asked her views on hanging by a Conservative Party worker while waiting to hear about her mother who had just undergone an operation. Iris Bentley, 65, died from cancer days later without knowing whether her brother had been pardoned.
Maria Dingwall, 34, said: "I just couldn't believe they were asking me. I told them I was Derek Bentley's niece and they didn't say anything. I felt quiet shocked."
Derek Bentley was hanged after being convicted of taking part in the murder of Pc Sidney Miles in 1952 during a bungled burglary in south London. Christopher Craig, 16, his accomplice, fired the shot that killed the policeman, but officers claimed that Bentley had called out "Let him have it, Chris." Bentley insisted that the police concocted the phrase.
The jury recommended mercy for Bentley, an epileptic with a mental age of around 11, but despite this he was hanged in Wandsworth prison, aged 19.
His niece, who is a Labour councillor, was telephoned in January by someone who said they were ringing from Conservative Party Central Office on behalf of Dame Angela Rumbold, a vice-chair of the Tory Party, and MP for Mitcham and Morden, south London.
She was asked whether law and order was a key election issue. "When I replied that it was the first questioned they asked me was whether I was in favour of capital punishment. I couldn't believe they were asking me that question, it seemed so insensitive."
A spokeswoman for the Conservative Party said: "It was a mistake, we took the name from the electoral register."
It was also disclosed yesterday that solicitors acting for the Bentley family are to submit new evidence to the Criminal Cases Review Commission which they claim will show it was a miscarriage of justice.
The new evidence includes statements from witnesses and those involved in the trial casting doubt on police testimony.Reuse content