I have to apologize right away for that headline. But it is hard to resist the urge to use the "what have you been smoking?" joke when discussing California Attorney General Jerry Brown's recent comments on marijuana, since Brown is talking such patent nonsense.

Of course, Brown's got a good reason to be doing so: he's running for Governor. And no prominent Democrat in the state has so far come out in support of Proposition 19, which will (if it passes) legalize, tax, and regulate recreational (as opposed to medical, which is already legal) sales of cannabis to California adults, in much the same way alcohol is regulated and taxed. Democrats have been shy of politically supporting such things ever since Nancy Reagan did her "Just Say No" thing decades ago. Democratic politicians can easily visualize the ads which would run against them if they took such a stand: "Jerry Brown wants to teach your six-year-old daughter how to roll a joint!!!" So it's not really surprising that Brown has come out against the idea.

But he really needs a better reason for doing so. Because the one he gave recently (to an association of district attorneys) is just ridiculous on the face of it. Here's the quote that local television station KSBW ran from Brown's address, to explain his reasoning for not supporting Proposition 19: "Every year we get more and more marijuana and every year we find more guys with AK-47's coming out of Mexico going into forests and growing more and more dangerous and losing control."

This might seem logical at first glance, but once you stop to think about it for a moment, it is revealed as sheer lunacy. Brown is right, there is a problem in California with both marijuana smuggling from Mexico and with Mexicans growing huge plots of marijuana on remote areas of federal lands (parks and forests). They began doing so because during the 1980s and 1990s, drug warriors were confiscating people's property when they found marijuana growing on it. Grow it on federal land, the growers reasoned, and confiscation of property isn't an issue (since the government already owns the land).

But Brown is saying that this problem is going to get worse if California legalizes pot. Which is, laughably, exactly the opposite of what will actually happen. Which is why Brown really needs a better reason for his political position on the issue.

Most of the price of marijuana, due to its illegal nature, is paying for risk. Because the guy who grows it, the guy who transports it, and the guy who sells it retail are all risking quite a bit by doing so (I'm not talking about medical marijuana here, I should point out, just recreational). In fact, a RAND report just out pretty much confirms what the thinking on this has been all along: ninety percent of the street price of marijuana pays for this risk. Which means (taxes aside) that if marijuana was legalized, the price would drop by a factor of ten. The folks at RAND estimated that the price would drop from $375 an ounce to $38 for the same amount, if Proposition 19 passes. This is exactly what happened to the price of gin when Prohibition ended. It dropped to one-tenth of what it used to be when the only place you could buy it was from a mobster.

This doesn't count taxes, of course. People are talking about taxing this amount at $50, but it's unclear exactly what the tax level would end up being -- say a total consumer price of around $90 to $100 an ounce, as a rough estimate.

But here's where Jerry Brown is wrong -- how many mobsters today bootleg liquor? Not too many. Why not? Because it simply is not worth their time to do so anymore. Without the premium placed on liquor due to the risk of it being illegal, the insanely-high profits disappear. And so the mobsters move on to other things which are still profitable because they are illegal -- like running numbers games (which the government then co-opted with an official lottery... the mobsters actually have to keep ahead of what is legal quite a bit, when you think about it).

This is exactly what would happen to the problem of Mexicans and marijuana in California. How could they compete with such reasonable prices? It simply would not be worth the effort to smuggle weed across the border, or to go live in a remote forest for six months to grow it inside of California. The Mexican drug cartels would move on to more profitable ventures, just like the mobsters of the Roaring Twenties did after Prohibition ended.

In plain language, legalizing marijuana would not just reduce, but likely utterly eliminate the problem which Jerry Brown cites as the reason he is against legalizing marijuana. Remove the profit motive, and you remove the illegal cartels from the business itself.

Now, I do not fault Jerry Brown for his stance. He is, after all, trying to get elected. So far the polling on Proposition 19 shows that it's going to be a very close race. Brown doesn't want to antagonize one side of the issue, which is perfectly understandable for any politician who is in a close race himself. Senator Barbara Boxer, the Democrat in the other big California race this year (to retain her seat), also does not support Proposition 19.

But Jerry really needs to come up with some better reasoning for his stance. Because anyone who can see through the ideology on the issue knows Brown's stated reasoning is not just faulty but downright backwards. Leaving voters to wonder (once again, I just can't resist) what exactly he's been smoking lately.

-- Chris Weigant

Follow Chris on Twitter: @ChrisWeigant