A teenager was recruited by Sean Mercer, Rhys Jones’s alleged killer, to help him to get away because he knew he was a vulnerable young man who lived in fear of the gangs, Liverpool Crown Court was told yesterday.

The 16-year-old youth, identified only as Boy M, had refused to leave home for two years since he was branded a “grass” and beaten up by members of the Croxteth Crew gang for naming names in an earlier police investigation into a shooting.

The youth, who has suffered from attention deficit hyperactivity disorder since he was a child, was frightened of being attacked if he left the safety of his family council house.

Tim Clark, counsel for Boy M, suggested that he was regarded as a “grass”, which his mother, giving evidence, agreed was a dangerous thing to be in the district of Liverpool where they lived. Mr Clark said: “From that point on it was his belief he was at risk of serious harm from former friends . . . he did not go to school and would not leave the house on his own. He would not want to be left in the house alone.”

Meanwhile, his health deteriorated. He became a virtual recluse, stopped taking his medication and lost so much weight that he was reduced to “skin and bone”, the court was told.

The court was told that Boy M’s mother came under intense pressure to change her story to the police. The jury heard recordings picked up by a listening device placed in the family home in which the mother could be heard arguing with another woman, later identified as Marie, the mother of Nathan Quinn, said to be a member of the Croxteth Crew gang.

Boy M’s mother could be heard saying: “If Mercer has got nothing to hide why is he saying he wasn’t here?” Her son is heard swearing at her and the other woman repeatedly urging her to change her story.

A woman tells her: “The lads have all got alibis” and urges her to tell police that she had mixed up dates and got the wrong day. “I think you better think again,” she says.

At one point on the tape, which is peppered with expletives, a male voice is heard to to say: “I am going to be away for f***ing years.” Boy M’s mother agreed that her son was “terrified” of what would happen to him after the trial. She was accused yesterday of lying to police in an attempt to support her son’s alibi. She said that Mr Mercer was once a frequent visitor to their council house in Croxteth, Liverpool, but she had not seen him in the four months leading up to the 11-year-old boy’s murder.

The prosecution alleges that Mr Mercer was the hooded gunman who shot Rhys through the neck and then, as he lay dying, fled on his mountain bike to Boy M’s council house shortly before 7.30pm on August 22 last year.

The witness said that she was taking a bath when she realised that there was somebody at the front door and then heard her own mother shout upstairs to her grandson: “It’s Sean.” She heard the visitor going upstairs to join her son in his bedroom. It was about 7.20pm to 7.25pm, she said. The two teenagers were joined about 20 minutes later by Mr Quinn, 18, and James Yates, 20, also alleged to be a gang member. She said that Mr Yates was on crutches at the time and his companion was wheeling a pushbike. They stayed for little more than ten minutes before leaving in a beige or gold people carrier, leaving the two bicycles behind in the hallway.

After drying her hair, and putting on pyjamas, she took the dog for a walk where she was told by a friend that a little boy had been shot dead.

Boy M’s mother said that, after her son was arrested by police a week after the murder, Mr Mercer and another teenager arrived on her doorstep asking to see him. They questioned him about what the police had been asking him about, she said.

Yesterday he refused to join his six codefendants in the dock because, the jury was told, he did not want to watch his mother giving evidence.

She changed her written statement shortly before stepping into the witness box. Under cross-examination, the witness agreed that she had originally told police that her son had been visited that afternoon by another youth so they could watch the England international against Germany on the television. This was not true, she conceded.

Richard Pratt, QC, counsel for Mr Mercer, asked her: “You were telling a lie to support what your son said in interview [with police]?” She replied: “Probably, yes.”

Neil Flewitt, QC, for the prosecution, said in his opening that Boy M allowed Mr Mercer to use his mobile phone to summon another youth to help him to get rid of the gun, and that he got rid of his clothing and arranged for the collection and removal of the bicycle. The barrister said that Boy M accepted most of what was alleged against him, but insisted that he was not guilty because he acted at all times “under duress”. He acted “out of fear” of Mr Mercer, who had told him that he had shot a child and demanded his assistance in avoiding detection.

Mr Mercer, 18, of Croxteth, Liverpool, denies murder. He shares the dock with six others, including two juveniles, who all deny charges relating to the fatal shooting.

The trial continues.

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