A man who strangled his senile former gay lover because he could not cope with the strain of caring for him has been jailed for six years.

Hairdresser Dominic Dalton, 42, killed 79-year-old Bernard Murphy with a dressing gown cord at their home in Crown Street, Brighton.

He snapped after a row late one evening and admitted what he had done in a hysterical phone call to his mother, telling her: "I love him so much."

Dalton was charged with murder but halfway through his trial at Lewes Crown Court today he was cleared on the direction of a judge after legal argument.

He admitted the manslaughter of the pensioner, who suffered from dementia, on the grounds of diminished responsibility.

Earlier in the trial a jury had heard how the pair were once lovers but their relationship became non-sexual and Dalton acted as Mr Murphy's carer.

Michael Austin-Smith, prosecuting, said: "The dead man, Bernard Murphy, was approaching 80. He and the defendant had lived together for ten or more years.

"There is not the slightest doubt that the defendant was very fond of Bernard Murphy and he shouldered the responsibility of looking after him, and did so over a number of years.

"It is plain that it cannot have been an easy job that he took on because over the last couple of years Mr Murphy started to exhibit signs of senile dementia, which must have made the task of caring for him very difficult and frustrating.

"His condition was getting worse and certainly by October and November the defendant was saying to friends and family that he felt he couldn't help."

Dalton, who had become teetotal two years beforehand, was said to have stopped taking anti-depressants and had started drinking before the killing.

On the night of the killing Dalton, originally from Porthcawl in Wales, was said to have returned home from work with a male friend and there had been sexual activity.

After his friend left, Dalton's mood was low and he began drinking. He also made several phone calls.

When Mr Murphy returned from the pub later that evening there was a row. In the early hours Dalton strangled his former lover with the cord.

That night Dalton had told his aunt on the phone: "I can't cope any more. Bernard has been screaming like a baby."

After the killing Dalton rang his mother at 2.30am, crying hysterically and saying: "I have killed Bernard. I love him - I love him so much. I couldn't cope."

The court heard that Dalton later raised the alarm by calling on neighbours, who phoned the police, and the pensioner's body was discovered in bed under a duvet. Dalton told officers: "I admit it, I did it. I killed my partner.

"He kicked off about 10.30pm. He has got dementia. He just screamed and screamed. The dog tried to grab me, I hit the dog. Bernard came downstairs shouting and screaming and I poured him a large vodka.

"I put the cord round his neck and that was it, as I was pulling it round his neck. I said, 'You'll be in peace and leave me in peace'."

After several days of evidence and legal argument about Dalton's state of mind, Judge Richard Brown ordered the jury to clear him of murder.

Richard Anely, defending, said: "It is agreed that at the time of the offence he was suffering such an abnormality of the mind that his responsibility for his actions was impaired.

"Whether it was depression or an adjustment disorder, he was inherently vulnerable to stress.

"The condition led to a situation where he could no longer cope with Mr Murphy's condition or behaviour.

"He poses little or no risk to others. The offence arose out of a particular situation that is unlikely to be repeated. The only risk is to himself."

Sentencing, Judge Brown said: "I accept that the task of looking after Mr Murphy was not an easy one.

"But those who take on a carer's role take on a responsibility to care for that person and not to harm them.

"This court has to balance the requirement to reflect the public horror of taking a life in these circumstances and recognise that the killing did take place at a time when responsibility was less than full."