Indeed they will. But if addicts have easier access to medically supervised maintenance doses (for instance), without risking jail time, then there may be less crime committed to feed these habits. Stuff I've seen has suggested that (for instance) when heroin users know where their next hit is coming from (the clinic) they are better able to handle their addiction and able to make some progress in the rest of life (hold down a job, etc).
I'm not saying I definitely have all the answers, the picture is complex.
That's extremely wishful thinking.
We currently have abundant access to alcohol and alcoholism is still a problem.
It's something I've read about coming out of the Swiss model, which medicalises heroin addiction rather than criminalising it.
I'm not going to hunt for references right now so I guess we'll have to agree to disagree.
In other words, even if it was not paid for, but just made available on prescription, chances are substantial proportion of users would be able to afford to maintain their addiction without much, if any, crime.
Oh can you imagine the horror!
"Our tax dollars are going on keeping them no-good junkies in smack! Not on my watch!"
Even if it was the best thing for law and order, for society, for everyone.... yeah I know, it'll just never fly.
Legalizing drugs will not make them free, and they will still lead to addiction.