Allthecoolnames, you're not a member of Victorias judiciary are you..??
Seriously though, no one is saying that Autism and depression are not real and can affect peoples behaviour. But it seems that every time someone is up before the courts these days, their defence is that it wasn't their fault due to some illness/condition/past treatment/ethnicity etc etc. Enough with the excuses!
People need to take responsibility for their actions. This person made a conscious decision to do this. Nobody is saying he should forever be judged and not given a chance to rehabilitate, but this was not some 'mistake' or error of judgment. It was a deliberate action and needs to be dealt with accordingly.
If found guilty, a bit of time away to reflect on the error of his ways is justified in this case, and may well deter others from doing the same thing. While he's inside, by all means provide the medical/psychological help he needs. Its not a matter of revenge. Its called making someone accountable for their actions. Something that has been sadly lacking in our court system of late.