Not at all. There are kids murderers out there. Recently one in France raped and then killed an 11 y/o girl. Somehow he was free although he'd already been involved in rapes. It's a big thing: there are protests all over France asking for actual laws actually doing something about rapists and kid killers.

To me the guillotine for a kid killer is way too nice: I'd go full medieval style, breaking his arms and legs while he's rotating on a vice. Then cutting his balls. Then finishing it by using horses to dislocate his body.

They used to do that in the middle-age.

From A to Z I'd be thinking about the persons you don't care about: the victims.

The problem is, as someone else mentioned, as soon as you give the state the power to kill people, they'll abuse it.

But, deep down, the harsh truth is very simple: leniency to rapists and murderers is cruelty to the victims, to their family and to their future victims (like just happened in France).

All those begging for leniency for criminals have the blood of that 11 y/o girl who got raped and killed by a repeat offenders on their hands.