A violent stalker who wrote love letters in blood to his therapist was jailed for life at the High Court in Aberdeen yesterday.

Brian Johnstone, 33, pursued Dawn Relton for more than two years. He took more than 1,000 secret photos and videos of her and vandalised her car, an incident that left the therapist shaking with fear. Police found a crossbow, handgun, smoke grenades and pepper spray when they searched his Glasgow flat.

Judge Lord Malcolm told Johnstone was too dangerous to be set free, despite the fact that no violent crime had been committed.

“Your conduct was in my view a very serious and worrying matter,” Lord Malcolm said. “I understand some may have concerns over the use of a life sentence where someone has not committed an offence involving direct violence, but research demonstrates the very significant harm this type of conduct has on its victims.”

In 2006 Johnstone, a mental health outpatient, was referred to Dr Relton , a psychologist at Maryhill Health Centre in Glasgow. He quickly became obsessed with the therapist, 30, admitting to having been “infatuated” and having sexual thoughts about her.

Dr Relton first became suspicious when during a therapy session, he asked for help with his camera phone, and unexpectedly took a photograph of her. A few days later, she found an anonymous letter and a gift of brooches at her home. A house key also went missing from her office.

Noticing Johnstone had become more nervous in her presence, she guessed he was responsible and stopped seeing him. Prosecutors argued that he viewed this as rejection and vandalised Dr Relton’s car, stealing its wing mirrors and wiper blades and slashing its tyres. The extent of Johnstone’s obsession was revealed after mental health nurses visited his flat in Arthur Street, Glasgow, last July and recognised a photo of the therapist on his computer screen.

Police were called and searched his home, finding the terrifying armoury, along with blood-stained handcuffs and a balaclava. The stalker had painted his victim’s name in either red paint or blood on his living room door and there were 1,100 photographs on his computer, of Dr Relton and others of Shona Crawford, one of Johnstone’s former work-mates. Albums of other photos showed Dr Relton’s house and car, and copies of messages that Johnstone had written in blood.

He pleaded guilty last November at Glasgow Sheriff Court to causing a breach of the peace by harassing Dr Relton between January 2006 and July 2008. His crime was considered so serious, sentencing was transferred to the High Court, and deferred for a year for psychiatrists’ reports. Forensic psychiatrist Dr Rajan Darjee said the stalker had a serious personality disorder, exacerbated by drug use.

He warned that “intimacy-seeking” criminals like Johnstone, who target healthcare workers, are very likely to strike again and to resort to sexual or physical violence.

Johnstone said he had no interest in Dr Relton’s life and apologised for causing distress. He added: “My intention was never to cause fear.”

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