A LECTURER who killed his wife after wrongly believing their two sons had been fathered by one of his friends is to be detained in the State Hospital at Carstairs without limit of time.

Robert Kerr, 39, inflicted more than 70 knife wounds on the body of his wife Xin Xin Liu, 39, at their suburban semi-detached home in Newton Mearns, East Renfrewshire, as the children slept upstairs.

A paternity test later proved his fears were unfounded and it was discovered Kerr was suffering from an “abnormality” of the mind when he carried out the killing in April last year.

The High Court in Glasgow heard yesterday that the family of trainee translator Ms Liu had been left devastated by her death.

Kerr, a former lecturer at West College in Paisley, had his guilty plea to culpable homicide on the grounds of diminished responsibility accepted by the Crown.

Lord Boyd told the High Court in Edinburgh yesterday he had to detain him to protect the public and to allow him to be treated for a serious mental illness.

The judge said: “I am satisfied that medical treatment is available that would be likely to alleviate the symptoms or effects of the disorder and that if medical treatment was not provided there would be a significant risk to your health, safety or welfare and to the safety of other persons.

“I am also satisfied that this treatment can only be provided if you are detained in hospital. Such detention requires you to be under conditions of special security and that can only be provided in the state hospital.”

He said Kerr must be detained “without limit of time” under Section 59 of the Criminal Procedure Act 1995.

Earlier, Lord Boyd said he had read a victim impact statement by the family of Ms Liu, who had moved to Scotland from China about 15 years ago to study law at Aberdeen University before meeting and marrying Kerr in 2003.

He said: “The impact on the family has been devastating. Nothing I can do or say can compensate for their loss.

“You were originally charged with murder. But the Crown accepted that your responsibility for your actions was diminished by reason of your mental condition at the time.

“I have considered the psychiatric reports and the report from the mental health officer. I also heard evidence from your psychiatrist.

“On the basis of this evidence, I am satisfied that you suffer from a mental disorder namely a delusional disorder. That appears to have been characterised by delusions about your wife’s fidelity and of police surveillance both of which were untrue.

“It is also clear that your heavy dependence on alcohol and drugs contributed your illness.”

Kerr had faced a murder charge when he originally appeared at the High Court in Glasgow.

As he was being held by police after the killing, Kerr told officers: “I found out tonight they were not mine.” He had contacted his GP complaining of stress to do with work and personal issues shortly before the killing, but later spoke to a nurse claiming he was feeling much better.