A Surbiton man accused of murdering his mother at her home claimed “she always hated my guts” and believed she may have been poisoning him, a court has heard.

Sean Heiss, 30, strangled his mother, Margot Sheehy, to death in June 2012 at her flat in Springfield Road, Kingston. He denies murder.

An Old Bailey jury was told today that Mr Heiss stopped taking anti-depressant and anti-psychotic pills four months before his mother’s death.

He had been diagnosed with a form of schizophrenia at the age of 20. But, following a period of stability at work and use of medication, he began taking it inconsistently.

He visited his GP a number of times between 2009 and 2011, and at one point was judged “severely depressed”.

He eventually stopped engaging with medical professionals, and stopped taking medication altogether, in February 2012, the court was told, but this was not flagged to mental health workers.

Mr Heiss, who worked at Waitrose in Richmond and had struggled with his finances and was in debt, told forensic psychiatrist Dr Mehdi Veisi during an interview that he became suspicious of Ms Sheehy after she refused to give him money.

He said: “I don’t think she wanted me to live independently. I don’t know why. I didn’t have money to eat.”

In order to get money Mr Heiss had even posed nude for a life-drawing class, Dr Veisi told the court.

Dr Veisi said Mr Heiss had further told him: “When I started living in Surbiton she started hating my guts. She always hated my guts on some level.

“How could she let her son starve? There was food at her flat that I could have.

“I was going there for coffee and TV. And she stopped buying coffee and sugar.

“I felt paranoid that she was poisoning me. Maybe with pills and potions, or maybe she put something in the big bottle of Coke I had left in her fridge.

“I don’t know what she did to me but I didn’t confront her. You can never get the truth out of someone who’s poisoning you. They don’t show their cards.”

Dr Veisi said: “You have this person giving up his medication, his views on the world completely change.

“He feels his mum is poisoning him. Feeling that his mum is deliberately humiliating him.

“That shows a person who is extremely suspicious and paranoid towards the sort of outside world.”

Mr Heiss recounted in his interview the way he felt on the day he killed his mother.

He said: “I can’t remember fully. I woke up and started drinking. I blacked out during the actual incident.

“She was saying that I was stupid. I was hungry. I asked for money and she said ‘no’. We argued for a few minutes.

“The next thing I remember is that I was sitting on the ground and I was looking at her dead body.

“There was blood and she was lifeless. I checked her and she wasn’t breathing.

“I was there for half-an-hour to an hour. I panicked and I took her card and I was trying to get away. I didn’t know where I was going.”

Eventually, as the court heard last week, Mr Heiss reached Barcelona, where in September 2012 he killed another woman, Clementina Nauta Liscano.

Surrey Comet: Sean Heiss, is accused of murdering a Spanish woman at this intersection in Barcelona. Pic: Google Street Map March 2014

Barcelona: Mr Heiss killed a woman at this intersection

Dr Veisi said today that Mr Heiss recounted to him being followed by men he believed were gay, and that he was afraid of a gang of Moroccans in the country.

Mr Heiss told him: “I often get followed by gay men and men who look homosexual, it’s not my imagination. They’re interested in my boyish look.”

He thought a man walking behind him in the street, wearing a diamond stud earring, had been following him and speaking on the phone about him, the court heard.

This was “based on a delusional belief, rather than being a reality”, Dr Veisi said.

The trial continues.