A slow-motion replay is just 1 way of "looking closer". The thing is, in order to not be hypocritical, we'd need to look as closely as possible. Once we do that, we'll be looking at the molecular structure of not only the brain of the perpetrator but also the whole body (as there is of course infinite interaction). We'll be asking for the causes that led to the body being as it was at the moment of the thing will cur…
On the one hand, if the perpetrator is not "responsible", then it seems inhumane to punish them.
On the other, if the perpetrator has demonstrated that they cannot or will not abide by society's rules and we have no way of reprogramming them to do so, then the only rational response is to remove them from society. Permanently. And as early as possible in their career.
And fortunately, questions of "inhumanity" do not arise---we don't have any free will to worry about, either.