We have had the same problem in Italy for many years now, and even though law doesn't make provision for life sentence, and penalties always take into account the seriousness of injuries (but also, to a lesser degree, the seriousness of injuries the attack could have caused if successful), tribunals apply every aggravating factor, penalties are summed up and despite the maximum penalty for a single offence with serious permanent damage is twelve years, the most ruthless offenders ended up being sentenced to more than twenty years, plus many years of mandatory psychiatric and social rehab after release.