Sounds like that figure only includes the revenue from sales taxes and retail fees. What about the savings from not having to enforce existing pot laws (not sure how much this is really a big deal in CA), and the increase in jobs and economic activity for all the agriculture and distribution businesses that would jump into the market. I'm guessing the overall economic impact on the state would be huge...like creating several Googles overnight.
On the other hand, I think a lot of estimates on what marijuana taxes would take in are overestimated.
In any case, enforcement savings would long before taxes. Possibly alone. Outright legalisation is rarely really on the table. It's decriminalisation of personal use, reducing it to rarely enforced minor infringement or something along those lines.
You can't expect the full suite of benefits from that. You save quite a lot on enforcement and incarceration. Mostly, the proponents want that to go into treatment.
But you still have associated crime, Criminals still control the industry. You don't get any taxes.
Pot is decriminalised in the Netherlands but the coffee shops where it is sold are in a quasi-legal gray area. Nevertheless this seems to have worked out OK for the dutch in terms of both permit revenue and taxes.
As pot smoking is a fairly social activity, I think many people would happily buy it over a counter - although ironically, California's strict anti-smoking laws might be a bigger barrier to the spread of such establishments. Personally, I much preferred the Dutch model - same way I can buy beer at the supermarket, and it's better value, but oftentimes it's nice to go to a bar and get it on tap. Bars don't seem to be limited by the existence of liquor stores.
The crime is there because the only way to get marijuana is illegally. A market exists. Profits exist. Anyone serving that market is by definition criminal.
Decriminalising personal use (but not sale, import, cultivation, etc.) doesn't fundamentally change that.
