DNA found on tights used to strangle a teenage girl 37 years ago was left at the time they were being used as a ligature, a court has heard.
Angus Sinclair, 69, is on trial accused of raping and murdering Christine Eadie and Helen Scott, both 17, who were last seen at the World’s End pub in Edinburgh on October 15 1977.
He denies carrying out the attacks along with his brother-in-law Gordon Hamilton, who is now dead.
The trial at the High Court in Livingston resumed this morning after it was halted yesterday when several members of the jury fell ill.
Forensic scientist Geraldine Davidson, giving evidence for a fifth day, talked the court through analysis of samples of DNA found on tights recovered from Helen’s neck.
Ms Davidson, who works with the England-based company Cellmark, told the jury the pattern of the DNA fitted with it having come from someone who was in contact with the material at the time it was being used to strangle her.
She said: “In our opinion this is as a result of this material having been deposited over the tights when the tights were wound in their position for use as a ligature and not as a result of the material having been deposited over the tights when the tights were being worn normally.”
The court heard it was “in excess of a billion times more likely” that the DNA came from Hamilton rather than another person unrelated to him.
Jurors have previously heard that Christine’s body was found at around 2.25pm on October 16 1977 at Gosford Bay, Aberlady, and Helen’s body was discovered at around 6pm that day in a field near Haddington in East Lothian.
They have heard a defence report detailing Sinclair’s version of events, in which he said he had “consensual sexual intercourse” with both girls in a vehicle in Holyrood Park and later left to go fishing.
He claimed the girls were “alive and unharmed” when he left them.
Sinclair has submitted three special defences of incrimination - blaming the deceased Hamilton; alibi - saying he was fishing on the banks of the Firth of Forth near Cockenzie power station at the time; and consent to sexual intercourse.