Sydney and a large number of other cities about the globe have injecting centres and decades of public reporting on crime, death, etc. in the vicinty of such centres.

They're an interesting middle ground - dedicated medical centres that allow users to inject with clean needles, test drugs for purity, and have narcan and crash carts available for complications.

You arrive, show ID, inject your drugs, chill for 20 minutes or so, and then leave.

The long term results are no increase in crime, reduction in death from overdose and dirty needle infections, HIV, etc, improvement in drug quality (now that the users can readily test quality there's more discernment in the market and a reduction in blatant over cutting bad mixes into the illegal supply).

Public drug use | shooting up is still illegal - this is reduced as there is a centre to go to, etc.

One other benefit is being able to easily and routinely survey drug users and adapt public policy to changing situations on the ground, early detection of changes in illegal supply, etc.

They cost money to run, they save money on reduction in public funds spent on the problems they reduce.