Whether a juvenile can be charged as an adult generally depends on their age (the younger they are the harder it is to charge them as an adult), their capacity to understand what they did, the severity of the offense, and their past history as a juvenile delinquent. The court will look at all of these factors and usually none of them will be determinative. The general presumption is that before people reach the age of majority they do not have the same capacity to form the wrongful intent to commit the crime as an adult does.
"The distinctive mark of the Christian, today more than ever, must be love for the poor, the weak, the suffering." Pope John Paul II
He should be charged with the crime, regardless of the age.
He will be charged with the crime, regardless of the age. The issue is whether he will be charged as a juvenile or as an adult. Because he's so close to the age of majority and the crime was so evil and so clearly premeditated, I would be shocked if he wasn't eventually charged as an adult. If he was 11 or 12, he'd probably just be charged as a juvenile regardless of the offense.
"The distinctive mark of the Christian, today more than ever, must be love for the poor, the weak, the suffering." Pope John Paul II