Sometimes the compassion the Buddhism has to be set aside to rectify what has been done. From my Islamic view, the only way he can be forgiven is if he asks for it, the mother gives it, receives compensation (blood money) and then be put to death.
Rectify? Don't you mean, sweep under the rug. The easy way out is to execute and wash your hands of it, like putting down a dog that bites. Becoming a murderer isn't genetic, just like a dog biting isn't, it is not something we can wipe out with a cull, it is something that must be addressed at the source. Until then there will always be murders.
There is no blood that needs to be spilled, or scales that need to be balanced. Executing someone is saying "We don't know how to deal with this, so we won't".
So now you have two dead and not a lot to show for it, things certainly are going well here. Who's next?
And no amount of rough livelihood should drive a mere teenager to kill a child in public. I don't believe that one bit. I don't care that they felt like garbage or had esteem issues. That's not an excuse to murder a baby.
It can, has and does. It's not that they felt a little bit upset or a little bit misunderstood, it's that they felt completely cut off and apart from society, just as members (and yourself - "I don't care") here are making them now. I never said it was an excuse for doing it or that they are not responsible for their actions, but it's probably the reason that led to them doing it.
EDIT: To
Pako, the manliest of all the Care Bears, can you see the similarity between what is happening? The robbery turned into a murder, likely because of sudden strong emotions on the part of the murderer - sometimes even a normal situation turns into a murder and the murderer cannot understand how they did what they have done.
For example, a husband walking in on his wife with another man, the husband experiences a sudden build up of sadness/anger that manifests itself as blind rage and the husband beating the guy to death - afterwards he cannot understand his actions. A normal, hardworking guy is now a murderer up for execution.
Then we have the group calling for blood - blinded by their sudden sadness/anger at what has happened, swift 'justice' must be had. As difficult as it is, remove the emotion and analyse the logical approach for dealing with this issue.