The son of a mother of 11 who was strangled to death 36 years ago has told a court how he kicked down her door after growing concerned about “the most horrible smell” coming from her flat.

Mary McLaughlin, 58, was found dead at her home in Partick, in Glasgow’s west end, in October 1984, Glasgow High Court heard on Tuesday.

Graham McGill 59, denies murdering her and fastening a ligature around her neck with intent to rape on September 26 or 27 that year.

Giving evidence on the first day of the murder trial, one of Ms McLaughlin’s sons, Martin Cullen, said he would visit his mother weekly at her third-floor flat in Crathie Court on Laurel Street.

He told jurors how he went to his mother’s home on October 2 1984, with his ex-partner and his child, saying: “We noticed that the hall light was on and there was a strange smell coming through the letterbox.

“She would never have the light on, never.”

Asked by prosecutor Alex Prentice QC to describe the smell, he said: “The most horrible smell you will smell in your life.”

Mr Cullen went on: “I knocked on the window and shouted through. I ended up kicking the door in.

“My partner went in and came out screaming. I went to the end of the hall and I could not go any further.”

He said he then phoned an ambulance and the police arrived.

Under cross-examination by defence counsel Sarah Livingstone, Mr Cullen said he remembered his mother “was afraid” around a month before her death.

McGill sat hunched in the dock wearing a light-blue rain jacket during Mr Cullen’s evidence as the trial opened.

He is also accused of stealing a set of keys from Ms McLaughlin’s flat.

The court heard Ms McLaughlin was last seen alive on the evening of September 26 drinking at west end pubs including the Hyndland Bar before leaving at about 10.45pm to go to a chip shop on Dumbarton Road.

Former taxi driver David Seager, 63, told the court he was working on Wednesday September 26 and had seen Ms McLaughlin playing dominoes in Hyndland bar when he took a break and got a soft drink in the venue.

He said he later saw her walking alone barefoot past his taxi looking “drunkish” and carrying her shoes under her arms on her way to the chip shop.

Mr Seager then told the court he saw a man cross the road and walk behind her on Dumbarton Road, agreeing with Mr Prentice that he formed the impression she was being followed.

He said: “It looked kind of funny, every time Mary walked away he was always behind her.”

According to his statement given to police in 1984, Mr Seager described the man as around 5ft 8in to 5ft 9in, 25 to 26 years old, skinny built with long, straight, black hair and clean shaven.

A post-mortem examination carried out on October 2 found Ms McLaughlin died of ligature strangulation at least five days previously, jurors heard.

The level of alcohol in her blood indicated she was “grossly intoxicated” at the time of her death, the court heard.

The trial was told that Ms McLaughlin was unemployed, had previously gone by surnames Cullen and Mullen, and had 11 children by two different partners.

McGill was arrested by officers in December 2019 and charged after police interview, the court heard.

He also faces a separate charge of threatening to murder Suzanne Russell and children at a house in Motherwell, North Lanarkshire, between January 1 1985 and December 31 1988.

The trial, before judge Lord Burns, continues.