but for this particular case, the guy is already a drunkard and even before the case of the child killing (or torturing), he used to beat up his wife already.

So the circumstance that the father is a drunkard should be a mitigating circumstance. And I wonder why it is being avoided in the discussion, what's the bias?

Again, I ask, will a sober man do such barbaric actions? Will a NORMAl (SOBER) person do such thing?