Just imagine if politicians got involved. It would need a registry, taxes, a bureaucracy of its own, licensing, limiting and any number of rules. Probably ID cards, too. I hate the political approach. So long as the business is decriminalized, it's OK by me. There's currently a lot of pragmatism going on, which spells real democracy.
As for which Party will do this, apply the only sensible rule: In an elected democracy, a Politician or Political Party has two rules: get into power, and stay in power. Anything good, or bad for society as a whole, which follows this, is purely a by-product of these rules. If it gets votes, they'll do it. If it loses votes, it's gone... They'll lie, bend the truth, buy votes, slander the opposition, muzzle the press - not just the current lot, either. It's inherent in the process. Ideology is playing to a support group to start with, and then - screw them!
PS. Vote for terpene!!!