Lothian Murder Files: Triple murder a tale of shame and breakdown

In fact, behind the appalling hammer attacks on 86-year-old Sarah Smith and her grandchildren, Scott Anderson, 13, and his sister Elaine, 16, pictured, was a tale of shame, mental breakdown and tragedy.

David Anderson, the teenagers' father, was by all appearances a quiet, devoted family man. He had worked as a bus driver out of the Longstone depot before setting up as a driving instructor 1969. He and his wife Dorothy were regulars at the Dublin Street Baptist Church.

Tragedy had already struck the family – their other son, Martin, had died aged 12 of Hodgkin's disease in 1965.

David Anderson had a desperately sad background of his own. His father had taken his own life "violently" and his sister had also committed suicide, while his mother had died of cancer. He struggled with severe depression throughout his life and, at the time of the killings, felt under huge pressure because of financial worries and a bout of flu. Psychiatrist Dr Robert Kennedy said at Anderson's trial: "He felt the only way out was to destroy himself. He first thought of suicide . . . he also thought of taking his family with him. He felt he wanted to spare his family the consequences of the financial difficulties he thought he had got himself into."

It was on 11 January, 1972, that Elaine's 19-year-old boyfriend became worried as the Andersons' phone at their East Brighton Crescent home was continually engaged. The teenager went to the house but when he failed to get any answer, he contacted his father, who called the police.

When they broke in, they found the bodies of Sarah Smith, who was almost blind and confined to the house, and her grandchildren, but Mrs Anderson was clinging to life. Her husband had attempted to take his own life but failed.

He was eventually acquitted of the triple murder on the grounds that he was insane and was sent to Carstairs State Mental Hospital for an unlimited time by the High Court in Edinburgh.