Killer Darren McGrath yesterday failed in a bid to have his minimum 14-year jail term slashed.
The application to the Court of Appeal was thrown out by judges after they had considered the merits of the case.
In June this year, the 18-year-old, of Essex Mead, Hemel Hempstead, pleaded guilty to the murder of Billy Dove, who was killed by a single stab wound to his chest in November last year during a late-night incident in Hemel Hempstead town centre.
Billy’s dad Paul Dove said: “I don’t believe McGrath will ever understand what he has taken away from me and the hurt and destruction he has caused my family and Billy’s close friends.”