Dr Robert Hardcastle, an expert in document analysis, also agreed that a purported confession extracted from the late Patrick Molloy would have had to be recorded at an unusually high speed if the timings on the document were accurate.
The developments came on the second day of the appeal on behalf of the Bridgewater Four against their 1979 convictions for the killing of the 13-year-old, newspaper delivery boy which were based largely on the Molloy "confession".
Michael Mansfield QC, counsel for Mr Molloy, told Lord Justice Roch and Mr Justices Hidden and Mitchell that Regional Crime Squad detectives had not given a true version of how the crucial confession statement had been obtained and that Mr Molloy, a "victim of oppressive questioning by the police which finally broke his will", had been denied access to a lawyer until after he was charged with murder.
James Robinson, 63, and cousins Michael Hickey, 35, and Vincent Hickey, 42, are on unconditional bail after an 18-year campaign to clear their names but want their convictions formally quashed by the Court of Appeal.
Dr Hardcastle, who was consulted by Merseyside police during earlier inquiries into the case and called as a Crown witness yesterday, was questioned over an electro-static deposition analysis (Esda) test he had conducted in relation to the statement purportedly from Vincent Hickey which Mr Mansfield claims police used as part of a deliberate strategy to provoke Mr Molloy into confessing. The test, which shows up indentations of writing, revealed that the statement had been written on paper resting immediately on top of the "confession", the crucial exhibit 54 in the 1979 trial.
Dr Hardcastle said after checking the handwriting of a number of officers, that the writing of Det Con Graham Leeke on the portion of the statement that had been preserved was the closest to the indentations on exhibit 54. Asked by Mr Mansfield whether he agreed with Robert Radley, the independent expert called by the appellants, that the evidence was consistent with it having been written by DC Leeke, Dr Hardcastle replied: "Yes". He also said the signature in the impressions was different from Vincent Hickey's and, again agreeing with Mr Radley's evidence, said the writing of Det Con John Perkins was closest.
According to the officers' version of events, Mr Molloy made the confession during an interview with DCs Perkins and Leeke between 3.40 and 4pm on 19 December 1978, with Det Sgt John Robbins taking notes. The confession was then dictated, written, signed and read back between 4pm and 4.20pm.
Dr Hardcastle told the court that he had researched the speed at which writing could be made during police interviews, and had found variations from 44 to 155 characters per minute. If the timings in police records were accurate the statement from Mr Molloy would have to be recorded at 170 characters a minute but this, Mr Mansfield told the court, took no account of the fact that Mr Molloy was a slow speaker and pauses.
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