Decriminalizing is a different matter from legalizing medical uses.

An inset at the first link in the thread lists the 13 states that allow some medical use. Each of the 13 has its own set of rules, and I haven't seen a comparison of what's allowed by each state. I suspect that it wouldn't be too hard to search something out.

The "states rights" argument on medical use has some strong advocates, and aympathy from quite a few people.

Decriminalizing has it's best arguments simply from the very large numbers of people overcrowding the jails for "offenses" that many people consider rather "petty," and from the complete lack of any evidence that penalties on "small fry" have accomplished anything very useful.

Study: 1 in 31 U.S. adults in prison system doesn't mention how many are from "petty drug" busts, but the common perception is that it's in large numbers.

John