Police ombudsman finds police were 'rigidly' fixed on theory that Lesley Howell and Trevor Buchanan killed themselves

A police investigation into a double murder in Northern Ireland, which was originally labelled incorrectly as a suicide pact, was deeply flawed, the police ombudsman has concluded.

The report into the deaths in 1991 of Lesley Howell and the police officer Trevor Buchanan found that detectives were "rigidly" fixed on the suicide theory. As a result the victims' killers ? the dead pair's respective partners ? almost got away with the murders.

Colin Howell and his former lover Hazel Stewart are both in jail, convicted of the double murders only because he confessed to the killings nearly two decades later.

The original Royal Ulster Constabulary inquiry was re-examined after the families of Lesley Howell, 31, and Buchanan, 32, complained.

The case was reopened when Colin Howell confessed in 2009 that he had killed his wife and his lover's husband.

The victim's bodies were discovered in a fume-filled car in a garage at Lesley Howell's father's house in Castlerock, County Derry, on 19 May 1991.

The police ombudsman found a litany of mistakes in the RUC inquiry.

The report found that forensic evidence was not gathered, injuries to Buchanan's face were not documented and inconsistencies and lies told by Colin Howell and Stewart were not challenged.

It also discovered that key information given to the RUC by a witness ? who said Colin Howell was giving his wife medication, had financial troubles and had previously dropped a live electrical cable into her bath ? was ignored.

The ombudsman suggested that a "golden hour" was missed in maximising evidence at the garage in Castlerock.

It said no fingerprints were taken and key pieces of evidence were not forensically examined. These included a vacuum cleaner hose pipe attached to the car exhaust and a cassette player and photographs found near Lesley Howell's body. The report noted that no scene log, sketches or measurements were taken.

It added that "peculiarities" at the scene that suggested foul play were not fully investigated. Buchanan's leg was hanging out of the car door and the driver's window was open.

The awkward position of both bodies and the loose fit of the vacuum cleaner pipe should have been "light-bulb moments", the report said.

It also highlighted the fact that even though Colin Howell and Stewart were caught lying about their affair, senior RUC detectives accepted their stories and ignored concerns raised by one police officer who thought the deaths were suspicious.

The Police Service of Northern Ireland (PSNI) said it accepted the findings of the report and apologised to the families of the victims.

In a statement, it said: "Police would also wish to apologise again to the Buchanan and Howell families for the failures and shortcomings of the 1991 investigation.

"In addition, PSNI will conduct a review of its current procedures to ensure that sudden deaths are subject to thorough investigation."

The Buchanan and Howell families said they were deeply saddened and disturbed by the failures of the original investigation.