Bring back hanging, get the scum off the streets Sean Mercer's mother Janette, 49, was due to begin trial at Liverpool Crown Court this morning when she changed her plea. Mercer, of Good Shepherd Close, Croxteth, admitted she was guilty on four counts of intending to pervert the course of justice. None of the facts were opened during the short hearing. Recorder of Liverpool, Judge Henry Globe, extended her bail and warned she now faces a "lengthy" custodial sentence. Outside the courtroom, Sky News reporter Tessa Chapman said: "You could barely hear her in the dock, because she was speaking through tears. "She said that she lied on a number of occasions about the bike that her son owned." Janette Mercer had been in the courtroom during her 18-year-old son's trial, when he denied owning the mountain bike. She had then repeated the denial in a written statement. Mercer has been bailed until April 1 when she will be sentenced. Judge Globe told her barrister Nigel Power: "She is completely guilty of a serious offence. "I have agreed to a pre-sentencing report being prepared but I cannot envisage passing anything other than an immediate custodial sentence." Chapman said: "He added that may well be a lengthy one." Rhys' mother and father attended the hearing and sat side-by-side as they did for three months last year during the murder trial. Sean Mercer was jailed for a minimum of 22 years in December for murdering the schoolboy. Rhys, 11, died in his mother's arms after being shot by Mercer in the car park of the Fir Tree public house in Liverpool in August 2007.