Jeremy Bamber's lawyers have told the Court of Appeal that new evidence "destroyed or seriously weakened" six of the ten points which saw him jailed for the murders of his family.
The court heard claims that all of the prosecution's case against Bamber at his 1986 trial for the murder of five members of his family had now been destroyed or seriously weakened.
Bamber's counsel, Michael Turner QC, said at the start of a three-week review of his case by three judges in London, that certain material in the case had been "deliberately withheld so as to unfairly bolster the prosecution's case and secure a conviction".
Bamber, who was jailed for life, sat in the dock as his counsel outlined his 15 grounds of appeal.
Mr Turner told Lord Justice Kay, Mr Justice Wright and Mr Justice Henriques: "At trial, the Crown's case centred on 10 key points. All but four of those we suggest are either destroyed or seriously weakened by the material now available."
Bamber's case was referred back to the Court of Appeal by the Criminal Cases Review Commission, which investigates possible miscarriages of justice.
Bamber, who was convicted of five counts of murder at Chelmsford Crown Court in October, 1986, has always maintained his innocence.
The court heard how his mother, June, 61, and six-year-old nephews, Nicholas and Daniel, were shot dead in their beds at White House Farm in Tolleshunt D'Arcy in August, 1985.
His father Nevill was found slumped downstairs, while his sister Sheila Caffell, a model nicknamed "Bambi", was found by her parents' bed. Detectives initially suspected that Miss Caffell, who suffered from mild schizophrenia and who had not been taking her medication, had murdered her parents and sons before turning the gun on herself.
They arrested Bamber, who stood to inherit almost £500,000 from his parents' death, nine weeks later when he returned from a holiday in France.
His first appeal attempt was rejected in 1989.
The case continues
Published Friday October 18, 2002
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