THREE South Wales Police officers are to be charged with conspiracy to pervert the course of justice over their parts in the prosecution of two brothers whose convictions for murder were quashed last year.

The Crown Prosecution Service also announced that no officers would be charged over 'discrepancies' discovered in the use of police notebooks at Swansea police station during the investigation into the case. However, it emerged yesterday that 14 officers have already been disciplined over the affair.

Wayne Darvell, 30, and his brother Paul, 31, were freed last July following what the Court of Appeal referred to as 'a catalogue of criticisms and exposures' over the reliability of evidence in the case. The brothers spent six years in prison for the 1985 murder of a Swansea sex shop manageress. Paul Darvell was sentenced to 20 years and his brother to 15 years.

The CPS said that three officers, named by the force as Chief Inspector Alun Jones Thomas, Inspector Jeffrey Jones and Constable Michael Leonard Collins, were to be summonsed to face a charge of conspiracy to pervert the course of justice. The officers were suspended in February last year.

The decision to prosecute follows consideration by the CPS of a series of files from Devon and Cornwall Police officers, who were called in to investigate the safety of the Darvell convictions after doubts were raised by Justice, the legal lobby group, and Rough Justice, the BBC television programme.

The inquiry was expanded in October 1990 after the discovery of discrepancies in the notebooks and pocketbooks of other officers based at Swansea but not involved in the Darvell prosecution. One thousand notebooks were scientifically examined. Altogether, 87 officers were placed under investigation and 25 named in the files passed to the CPS, which covered the Darvell case and nine other prosecutions.

Announcing the decision to prosecute the three officers over the Darvell case, a CPS spokeswoman said that after taking advice from counsel the CPS 'has decided that with regard to the other 22 officers there is insufficient evidence to provide a realistic prospect of conviction for any criminal offence'.

Some of the 22 officers, including a further four suspended over the other cases, could still face disciplinary action.

The Police Complaints Authority said yesterday that in relation to the second part of the inquiry, 14 officers had already pleaded guilty to discipline offences, or had been found guilty at hearings. The punishments, which can range from dismissal to a reprimand, have not been made known.

A further 28 officers have received 'advice' or 'admonishment' over their conduct, a measure which falls short of formal discipline. Eight officers are not to face any action, six have left the force and 15 discipline cases are still to be resolved.