decriminalizing hard drugs, opiates specifically, is not going to save anybody's life, and the people telling you it will are peddling false hopes and nonsense.
we're probably better off redirecting the policing services. sure. there are other reasons to stop enforcing the law, even if it's kept illegal, technically.
but, the fact is that these drugs are going to kill the people that use them, regardless.
the exception is mdma. if you legalized mdma, you would save lives, because people that take mdma aren't intending to take something harder. but, it's not really a "hard drug" either. i made this point from the start. that is the drug you should target, not heroin and not coke and not even pot, really.
opiates, specifically, build up tolerance levels, so you need more and more to get high as you go. it follows that the sad truth is that it's just a matter of time, unless you deal with the addiction. we can talk about clean needles and all of these kinds of things as risk reduction in the context of cost reduction and that's fine, but giving addicts clean needles and clean drugs is still going to kill them, as the tolerance pushes past the lethal state.
you have to treat the addiction, and you can only do that if it's voluntary. that's what mitigation should be about.