Juveniles found guilty of murder in the US are given life, with no chance of parole - a hardline approach that in 2015 prompted the American Supreme Court to rule such sentences as 'unconstitutional'. With the system now under review, Susanna Reid travels to the US and talks to young killers about their crimes and life in jail - including one speaking for the first time since discovering he have the right to have his sentence reviewed. Susanna also meets the families of victims, to ask how they feel about a possible change to American's approach to juvenile sentencing.