John Cooper trial: Blood on shorts 'matched victim'
Blood on shorts found in the house of a man accused of two Pembrokeshire double murders matched a victim, a jury heard.
An expert told Swansea Crown Court the chances the DNA profile on the shorts in John Cooper's house was not that of Peter Dixon were one in a billion.
Mr Cooper, 66, denies killing Mr Dixon and his wife Gwenda in 1989.
He also denies the 1985 murder of brother and sister Richard and Helen Thomas, and rape, indecent assault and attempted robberies in 1996.
It is claimed Mr Cooper, a farm labourer from Letterston, shot Mr and Mrs Dixon at close range on the coastal path while the couple from Oxfordshire were on a camping holidaying in the area in 1989.
They were last alive leaving their campsite near Littlehaven on 29 June and their bodies were found nearby on 5 July.
The Thomases were shot at their house, Scoveston Park, near Milford Haven, in December 1985.
In his opening address prosecutor Gerard Elias QC told the jury a pair of shorts recovered from Mr Cooper's bedroom was found to have a blood mark DNA profile matching Mr Dixon.
On Wednesday forensic expert Dr Phillip Avenall told the court DNA profiles matching both Mr Cooper and Mr Dixon were recovered from the shorts.
He said the chances that the blood sample was someone other than Mr Dixon's was one in a billion.
The jury has also heard blood samples were obtained from a sawn-off shotgun found in a hedge near a robbery that Mr Cooper was convicted of in 1998.
Swabs taken from the gun also had a DNA profile that matched Mr Dixon's.
The trial continues.