Jurors in the Rhys Jones murder trial were urged to "consider carefully" the credibility of a key prosecution witness.
Mr Justice Stephen Irwin, summing up the case at Liverpool Crown Court, recounted the evidence of the star witness, who cannot be identified and is known as Boy X.
X claims alleged gunman Sean Mercer gave him the suspected murder weapon shortly after 11-year-old Rhys was shot dead outside the Fir Tree Public House in Croxteth, Liverpool, in August last year.
Mercer, 18, denies murder and says he was at a friend’s home watching a DVD when Rhys was killed.
Six others deny assisting an offender.
Mr Justice Irwin told the jurors: "Please concentrate on the credibility and evidence of (Boy X).
"You might on one view reach the conclusion that he was not blameless, worthy of being prosecuted rather than being given immunity.
"But that is not the point. The point is, do we believe the evidence he has given?"
After initially being treated as a suspect in the murder investigation, X was given immunity from prosecution in exchange for his account of the movements of Mercer and the Smith and Wesson .455 revolver which prosecutors say was used to shoot Rhys.
