As America reconsiders a failed cannabis policy -- as reflected in the drug's wide availability among the youth demographic, despite courts and jails crowded by non-violent users -- a central question regarding legalization or decriminalization is, "Will this increase or decrease the abusive use of cannabis?"

Surely the law dissuades some law-abiding people from trying cannabis at all. Say some old guy like Yours Truly decides to become a scofflaw and obtain some of this substance, for whatever reason. How would I go about it?

Since the kids have no trouble getting it, perhaps a local sports bar where collegians assemble would offer opportunities to "score."

I'd have to dress differently so I wouldn't be mistaken for a common hobo; how do college profs dress?

And then what? Sidle up to a group of kids at a bar, cast a sidelong glance around the room, then whisper out of the corner of my mouth, "Hey, ah, Duude. Know where a guy could get some weeeed?"

Yeah, that would work.

In fact, I don't know how it's done. So maybe legalization would allow or even encourage me to try it.

In principle, at least, that might be beneficial -- for my chronic pain. But some might exploit decriminalization just to get high and have fun -- recreational users, they're called.

More than a decade after the passage of the first medical cannabis law in California, a considerable body of data has accumulated to demonstrate no state with a medical cannabis law has experienced an increase in youth use since enactment of the law.

All these states have reported overall decreases in youth use, exceeding 50 percent in some cases, while nationwide, the trend is toward greater use.

Texas A&M researchers assessed whether passing medical cannabis laws encourages greater recreational use; they found, definitively, that it does not. "Our results indicate that the introduction of medical cannabis laws was not associated with an increase in cannabis use among either arrestees or emergency department patients in cities and metropolitan areas located in four states in the U.S.A. (California, Colorado, Oregon and Washington). ... Consistent with other studies of the liberalization of cannabis laws, medical cannabis laws do not appear to increase (overall) use of the drug."

Cannabis use rates as a percentage of the overall population vary only slightly among states, despite states' having remarkably varying degrees of marijuana enforcement and punishments. In fact, several states with the most lenient laws regarding cannabis possession -- such as Nebraska (possession of up to 1 ounce is a civil citation) and Mississippi (possession of up to 30 grams is a summons) -- report having some of the lowest rates of cannabis use, while several states that maintain strict penalties for personal users (e.g., Rhode Island) report comparatively high levels of use.

Contrast the drastically different policy approaches toward cannabis and tobacco.

Cannabis is illegal, thus unregulated and untaxed, funneling profits to organized crime. Tobacco is legal, therefore regulated and taxed, with part of the revenues going to education, treatment and prevention. Users pay their share of the cost of such programs.

Though America made approximately 860,000 arrests for cannabis in a recent year, including 760,000 for mere possession, teen use is on the rise. Without criminalizing tobacco per se, or making mass arrests of tobacco users, youth tobacco use has declined far below its 1996 peak. The two very different drug policies display two very different outcomes.

Medical cannabis, like any psychoactive drug, can be diverted for recreational use; we face that issue with opiates, stimulants and sedatives now. Prescribers must be vigilant.

But we as a society have made a commitment: The scammers don't get to call the shots. Scammers shouldn't prevent legitimate patients from accessing a valuable therapy.

When scammers divert opiates, Valium, etc., the results are often hardcore addiction and death.

Here's what happens when medical cannabis is diverted: People who were already using black-market cannabis now have a purer, safer product, they don't clog courts and jails, they don't jeopardize their lives and careers with possession busts, and they no longer do business with professional salesmen of more harmful drugs.

Call it harm reduction, at worst.

What to do? Our present approach is a destructive and expensive failure. Here are some conclusions I've reached during my exploration of the topic.

The simplest and most effective move would be to legalize, regulate and tax cannabis like tobacco and alcohol. The current patchwork of state laws is confusing and unfair. A uniform national policy would enormously facilitate the quality research we all agree is warranted. It would cut down on taxpayers' support of the lucrative but oppressive prison-industrial complex, and free law enforcement and the courts to pursue more pressing concerns. Tax revenues can support treatment and prevention, as we do now with tobacco, alcohol and gambling proceeds.

At the very least, cannabis should be removed from the Scheduled drug category, or moved to Schedule V status. This too would free researchers, and allow doctors and patients to consider the cannabis option.

There is much we don't know about cannabis, but what we already know provides a sufficient basis for informed, sensible policy revisions.

Jon Hauxwell, MD, is a retired family

physician who grew up in Stockton and now lives outside Hays.