These letters rarely if ever take on anything that might be controversial, of course. It’s always something that offends voters’ sense of morality, or inspires their revulsion — animal abuse, say, or those horrible alcohol-caffeine drinks aimed at the young. But that doesn’t mean the AGs are always right. The latest letter, aimed at gutting a crucial provision of the 1996 Communications Decency Act, starts out this way: “Every day, children in the United States are sold for sex.”

Well, that’s true, and it’s awful. But the solution proposed in the letter signed by 48 of 50 AGs is no solution at all, and in fact would be counterproductive, and meanwhile would stymie business on the Internet, if not render it impossible.

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The AGs want basically to rescind the CDA’s Section 230 so they can go after classified-ad sites, specifically Backpage.com, where ads for underage prostitutes sometimes appear. Section 230 is in no small measure responsible for the Internet as we know it today — for good and ill. It protects Internet service providers (like ISPs, search engines, classified-ad services, and pretty much every site on the web) from liability for what its users might do. If it didn’t exist, an ISP might be held liable for every bit of illegal content that passed through its servers, a newspaper’s website might be held liable for some bit of slander posted by a commenter, and Google (GOOG) might be held responsible for returning search results linking to some site that offers pirated movies.

None of those businesses would exist in their current form without Section 230. That’s why it was passed, almost unanimously, in the first place. Crucially, it allows Internet services to take action against users — such as removing offensive content — without legally transforming themselves into publishers of that material and thereby exposing them to liability. There is, therefore, a lot less offensive and illegal material online that there otherwise might be — difficult as that might be to fathom. In one case,
Zeran v. America Online
, the court noted that the “amount of information communicated via interactive computer services is staggering,” and holding service providers responsible for all of it would be impossible.

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As Mike Masnick of Techdirt notes, before Craigslist was pressured into dropping ads for prostitutes altogether, it was reliably helpful in helping law enforcement agencies track down and bust human traffickers. When Craigslist dropped the ads, that didn’t make the advertisers disappear — it simply sent them elsewhere, including to Backpage. Going after Backpage would have the same effect, because the Internet is limitless. “This,” Masnick writes, “is the crux of the issue: when you blame the service provider, rather than the actual law breakers, you don’t stop the law breaking. You just make it harder to capture the actual law breakers.”

That’s not stopping the AGs, however, since they don’t have to worry about such niggling considerations as the complete unworkability of what they’re proposing. They have come out against child prostitution, and that’s all that matters. And in doing so, they’re quite consciously and knowingly confusing the public that they have sworn to serve.

None of which is to say that outfits like Backpage should get an easy pass from the rest of us. The fact remains that the company is in the prostitution-services business (though of course other things are advertised there, too), and the fact is that child prostitutes are advertised there with some regularity. This is a terrible thing. But while we can and perhaps should judge Backpage for the business it’s in — just as we judge usurious payday-loan outfits or sleazy-but-legal cash-for-gold operations (or, for that matter, websites that seem to encourage awful behavior by users) — that doesn’t mean we should rescind a law that allows the web to work.