A POLICE force's failure to investigate a rape allegation for more than four years is to be examined by a watchdog.

The Independent Police Complaints Commission (IPCC) is to launch an inquiry into Dyfed-Powys Police's handling of a complaint made in April, 2005.

The situation only came to light earlier this year when the complainant, referred to as Ms X by the IPCC, appeared as a witness in a court case concerning an entirely different allegation of rape.

During the trial, the defence barrister cross-examined Ms X about her own allegation which had been revealed during the disclosure process.

Standing in the witness box, Ms X was unable to explain the outcome of her complaint because she had heard nothing from detectives after making a statement.

When the trial judge ordered the file containing the allegation to be found, officers were unable to locate it. A spokesman for the IPCC said this led to Ms X's account and credibility being "robustly challenged" by the defence barrister.

The file was eventually found, which contained the original statement and confirmed Ms X's recollection of events.

The file also contained a further allegation made by another victim against the suspect which had also not been recorded as a crime or investigated further.

The complaint, which is alleged to have happened in 1995 when Ms X was a child, is now finally being investigated by Dyfed-Powys Police.

Tom Davies, IPCC Commissioner for Wales, said: "Because of police failures this young woman was put through an unnecessary ordeal at a trial for which she appeared as a witness.

"But worse than that is the fact that having reported an allegation of rape the police did not properly investigate the allegations of two serious crimes.

"The intervening years will not have helped the evidence-gathering process. The public expect the police to investigate those crimes reported to them, and for crimes of serious sexual assault to be given a real priority.

"Rape is under-reported as a crime and we have to ensure that the public, and especially women and young girls, can have confidence that when they do report rape that it is dealt with sensitively and thoroughly.

"The IPCC investigation is a criminal investigation and will seek to ensure that we find out what went wrong in this case. I have set terms of reference for this investigation that also include making any recommendations necessary to ensure that lessons are learnt so that the public can have confidence that allegations are properly dealt with."

A spokeswoman for Dyfed-Powys Police said: "When the issues arising from this case initially came to notice, the force referred the matter to the IPCC.

"The force is co-operating fully with the IPCC investigation and will carefully consider its findings in due course."