The North's Police Ombudsman, Mrs Nuala O'Loan, has rejected any suggestion that police officers pressurised a forensic scientist into acting improperly, but was strongly critical of how police handled an attempted murder investigation.
Her inquiry follows concern arising from a court case against a suspected dissident republican charged with a gun attack on Draperstown polling station in Co Derry during the British general election in 2001.
PSNI chief constable Mr Hugh Orde referred the case to Mrs O'Loan following controversy surrounding the case, and the judge's criticism of how police handled forensic evidence.
Two police officers and a young girl were injured in the attack. The suspect was acquitted last September.
A key element of the Ombudsman's inquiry centred on the scientist's refusal of a police request to examine the suspect's clothes for evidence of cartridge discharge residue. She argued that the clothes were incorrectly packaged, and could have been contaminated by police.
The scientist said in court she was being asked to carry out work on which she could not properly comment because of the concerns of contamination.
The police officer involved told the Ombudsman that while he was aware the material was incorrectly packaged, he still believed the examination was required.
Mrs O'Loan, after receiving independent consultants' advice, found with the police officer that he was entitled to request the examination. The Ombudsman added that the scientist confirmed that she was not asked to provide false evidence in court.
Mrs O'Loan, however, was scathing in her criticism of the police investigation. She criticised the senior investigating officer, who was not fully trained, for leaving the scene of the crime after only 30 minutes, and generally for not establishing a forensic strategy. "Evidence was left exposed to the elements overnight, and to the possibility of loss of forensic value."
She also said that a scenes of crime officer did not conduct a thorough forensic examination. "He left the scene after 50 minutes without having undertaken a full forensic examination, taken photographs or secured any evidence."
Other criticisms included:
Mrs O'Loan said it would be wrong to penalise the senior investigating officer as he had not been fully trained, and it would also be wrong to criticise the first scenes of crime officer as he was a probationary officer at the time.
The two other scenes of crime officers had since retired. The senior officer has since been fully trained.
