A musician was stabbed to death on the doorstep of his own home by the "jealous, obsessive" estranged husband of a woman he was seeing, a court was told today.

John Britton had been rehearsing with two friends at Paton Close, West Kirby, on December 3, last year, for a forthcoming gig when he answered the door, allegedly to his love rival, Wayne Smith.

His friends heard him cry out in pain and found him lying in the hallway and a man with a goatee beard and spectacles standing over him "stabbing him with a knife."

As they shouted at him to stop, he raised the knife in the air and pointed it towards them causing them to flee to different rooms.

"When they emerged from the rooms the man was gone but it was clear that Mr Britton was in a very bad way," claimed Stephen Riordan, QC.

"The murder weapon, a knife, was snapped in two by the ferocity of the stabbing and the two pieces were found in the hallway."

Paramedics treated him at the scene and he was taken to hospital but was pronounced dead at 10.50 pm, an hour and 20 minutes after the stabbing.

A post-mortem examination revealed two serious stab wounds, one to the left side of the neck and the other to the left side of the chest and death was caused by shock and blood loss.

"What lay behind this murderous attack on a man whom you will hear appears to have been well liked by all and had no enemies?

"The prosecution say the case has a domestic background and the motive for this murder was jealousy and hatred of John Britton by Wayne Smith," said Mr Riordan.

He explained that Smith, 38, had been married for about two to three years to Sarah Arbon Smith with whom he had a daughter.

Previously Sarah had been in a relationship with Mr Britton.

It had ended before she began seeing Smith but in 2012 they resumed a relationship which led to her marriage breaking down and they separated.

Smith stayed in the matrimonial home and she moved in with her mother.

"There is considerable evidence that the defendant was unable to come to terms with the breakdown of his marriage," said Mr Riordan.

"He was jealous and resentful of Mr Britton whom he appeared to despise and he did not trouble to conceal this attitude from other people.

"More sinister, however, was his continuing surveillance of his wife using considerable technical skills."

He managed to access texts she had sent to Mr Britton, hacked into her Facebook account and used webcams in their home to spy on her intimate activities.

He also issued threats towards Mr Britton to other people.

Mr Riordan added that Smith "resented intensely" Mr Britton's relationship with his daughter. He described him as a "compulsive, obsessive individual.

The sort of individual who became utterly obsessed about the breakdown of his marriage and his estranged wife's relationship leading him to do what he did."

Smith, of Seymour Street, Birkenhead, is on trial at Liverpool Crown Court denying a murder charge.

Mr Riordan told the jury that Smith is a keen player of war games and got a fellow player and friend, Steven Hatton, to provide a false alibi for the evening of the killing, December 3 last year.

Mr Hatton, who is to be sentenced at a later date for assisting an offender and attempting to pervert the course of justice, is now a prosecution witness, said Mr Riordan.

He played a half hour compilation of CCTV footage showing Smith leaving his home before going to Mr Hatton's home where he allegedly got changed.

Smith, wearing a hooded jacket and snood partly covering his face, then caught a train to West Kirby and went to Paton Close where he loitered for a while and then left, returning half an hour later to commit the fatal attack, it was claimed.

He returned to Hatton's home in Elmswood Road, Birkenhead, and they went to a nearby chip shop "setting up his alibi," alleged Mr Riordan.

After his arrest Smith gave a prepared statement claiming he had been at Hatton's home all evening. Hatton later told police that Smith confessed to the stabbing to him. Mr Riordan said that a hood discarded in Grange Cemetery, West Kirby, on which there was DNA matching the defendant was found by a policeman.

The trial, expected to last two weeks, continues