Great series of articles about "how laws die."

Basically, they're ignored to death.

American lawbreaking: How laws die. - By Tim Wu - Slate Magazine:

"...It would then be up to the junior prosecutors to figure out a plausible crime for which to indict [celebrities.] The crimes were not usually rape, murder, or other crimes you'd see on Law & Order but rather the incredibly broad yet obscure crimes that populate the U.S. Code like a kind of jurisprudential minefield: Crimes like "false statements" (a felony, up to five years), "obstructing the mails" (five years), or "false pretenses on the high seas" (also five years). The trick and the skill lay in finding the more obscure offenses that fit the character of the celebrity and carried the toughest sentences. The, result, however, was inevitable: "prison time."

As this story suggests, American law is underenforced—and we like it that way. Full enforcement of every last law on the books would put all of us in prison for crimes such as "injuring a mail bag." No enforcement of our laws, on the other hand, would mean anarchy. Somehow, officials must choose what laws really matter."

But, but... ALL the laws really matter, right? I mean, that's what they tell me! Parents and TV and all those fine politicians...

Or civilization turns to anarchy! Cats lying down with dogs! The rules is all that keeps us from turning into animals! [And opposable thumbs, of course.] And hey, all the cops in the news, from the DEA to the DOJ on down tell you that they "just enforce" the law. They have no discretion or judgment in prosecuting, say, cancer patients for using medical marijuana. THEY HAVE TO ENFORCE THE LAW!

Of course.

For example - How laws die - Obscenity:

"In the Unites States, using a computer to download obscenity is a crime, punishable by up to five years in prison. Federal law makes it a crime to use 'a computer service' to transport over state lines 'any obscene, lewd, lascivious, or filthy book, pamphlet, picture, motion-picture film, paper, letter, writing, print, or other matter of indecent character.'

Under the plain reading of the statute, most men in the United States may be felons. Statistics on the downloading of "lewd pictures" are notoriously unreliable, but according to some surveys, 70 percent of men have admitted to visiting pornographic sites at some point. Many such sites are probably obscene under the Supreme Court's definition of obscenity—that is, they, according to community standards, "appeal to the prurient interest," depict "sexual conduct" in an patently offensive way, and lack "serious literary, artistic, political, and scientific value."

Today, despite these laws, there are very few prosecutions centered on mainstream adult pornography. Over the last decade, and without the repeal of a single law, the United States has quietly and effectively put its adult obscenity laws into a deep coma, tolerating their widespread violation with little notice or fanfare... This enormous transformation has occurred without any formal political action. And it illuminates just how America changes law in sensitive areas like obscenity: not so much through action as through neglect."

So, all you fellas out there, and you know who you are... Make sure you go turn yourself in, kay?

This next bit I found particularly engaging, in that we now have a HUGE drug legalization movement, all accomplished simply by changing the words we use. A little BS semantic shift, and voila! - drugs for everybody!

How laws die. - That Other Drug Legalization Movement:

"...drug legalization is happening in a wholly different way. Over the last two decades, the FDA has become increasingly open to drugs designed for the treatment of depression, pain, and anxiety—drugs that are, by their nature, likely to mimic the banned Schedule I narcotics. Part of this is the product of a well-documented relaxation of FDA practice that began under Clinton and has increased under Bush. But another part is the widespread public acceptance of the idea that the effects drug users have always been seeking in their illicit drugs—calmness, lack of pain, and bliss—are now "treatments" as opposed to recreation. We have reached a point at which it's commonly understood that when people snort cocaine because they're depressed or want to function better at work, that's drug trafficking; but taking antidepressants for similar purposes is practicing medicine.

...Are the new pharmaceuticals really substitutes for narcotics? The question, of course, is what counts as a substitute, which can depend not just on chemistry but on how the drug in question is being used. But as a chemical matter the question seems simple: In general, pharmaceuticals do the same things to the brain that the illegal drugs do, though sometimes they do so more gently.

As many have pointed out, drugs like Ritalin and cocaine act in nearly the exact same manner: Both are dopamine enhancers that block the ability of neurons to reabsorb dopamine. As a 2001 paper in the Journal of the American Medical Association concluded, Ritalin "acts much like cocaine." It may go further than that: Another drug with similar effects is nicotine, leading Malcolm Gladwell to speculate in The New Yorker that both Ritalin and cocaine use are our substitutes for smoking cigarettes. "Among adults," wrote Gladwell, "Ritalin is a drug that may fill the void left by nicotine." Anecdotally, when used recreationally, users report that Ritalin makes users alert, focused, and happy with themselves. Or as one satisfied user reports on Erowid, "this is the closest pharmaceutical *high* to street cocaine that I have experienced." In the words of another, "I felt very happy, and very energetic, and I had this feeling like everything was right with the world.""

Of course, it's all the same. People drink, smoke, take drugs, do extreme sports and even work out, for one reason. It makes them feel good. Exercise and sports dumps a massive amount of endorphins and adrenaline and pleasure drugs into your system. A hug or a kiss does the same thing. We all engage in all sorts of behaviors to engage these biochemical rushes, and then every society almost always arbitrarily, labels some good and some bad. Cocaine? Bad. Ritalin? Let's give it to the kids! Alcohol? Good! Marijuana? Bad. And on and on and on...

And I kinda really wanna try Ritalin now.