A rapist who brutally attacked a pensioner 16 years ago would have walked free but for a change in the law allowing retrials of suspects in exceptional cases, according to prosecutors.

Lawyers said Wendell Baker would never have been brought to justice for the rape of 66-year-old Hazel Backwell in the bedroom of her Stratford home but for the double jeopardy law.

Passed in 2003, the law allows those suspected of serious offences to be re-tried if compelling new evidence comes to light.

Baker, 56, was given a life sentence last week – having previously been acquitted in 1999. Prosecutors secured his retrial after a “one in a billion” DNA match surfaced.

Crown Prosecution Service lawyer Tony Connell said: “The change in the law allowed us to finally convict Baker for his appalling crime and I hope that it will have brought some sense of justice to Hazel Backwell’s family.”

Investigating officer Det Ch Insp Christopher Burgess added: “It was only the double jeopardy law which allowed us to secure the conviction.”

Baker was unanimously found guilty by jurors at the Old Bailey last Tuesday. He refused to attend his sentencing on Friday, where Judge Peter Rook said he would serve at least 10 years and six months before being considered for parole.

Ms Backwell, who died in 2002, suffered a “terrifying ordeal” when Baker broke into her home in Litchfield Avenue in January 1997.

He tied her hands behind her back with flex, beat and raped her, then ransacked her house before leaving her bound and trapped in a cupboard.

Ms Backwell was found by her neighbour the next evening, terrified and thinking she was going to die. She was left too afraid to continue living alone or go out by herself.

Judge Rook said Ms Backwell was beaten “black and blue” by Walthamstow resident Baker.