You a right here, this may allow the case to be called extreme. But I am not sure he deserves the death penalty.
Extreme outliers are often used to justify extreme measures. The question is, should they? In an EU country we had just a murder case, a teen was murders by two girls, aged 13 and 12. Since this is below of the age of criminal responsibility for the country, where they were committed, people argued the age for criminal responsibility should be lowered to 12 or even below. Are extreme outliers a good basis for this? And if age of criminal responsibility is lowered to 12 or 10, should not the "age of consent" be lowered to 12 or 10 too?