Spam these days is more than an annoyance—it increasingly carries malware payloads that can do serious damage to your PC, steal your identity, or turn your PC into a zombie that carries out denial of service attacks.

So anything that law enforcement can do to fight spam should be a good thing, right? Well, not quite, as I’ll explain.

Federal and state agencies have launched “Operation Slam Spam,” in which dozens of spammers, identity theft artists, and scammers have been arrested or will be prosecuted for doing the kind of slimy stuff that has become an online epidemic. Good thing, you might say. And I agree, at least partially.

Here’s the catch: Much of the money for the effort was paid for by a private business, and not just any private business, but by the Direct Marketing Association (DMA), an industry lobbying group whose members blanket your real-world mailbox with junk mail, and which has fought against stronger anti-spam laws.

So what’s wrong with that?

First off, prosecutions shouldn’t be bought and sold on the open market.

Then there’s the problem with the DMA itself. The reason it funded Operation Slam Spam is crystal clear: It hopes that a big-publicity prosecution will convince people that the laws on the books against spam are working, and all that’s needed is to use the law to go after the bad guys. If it can convince people of that, it will consider its money well spent.

The truth is, though, that the federal Can Spam Act has failed. Spam has been getting worse, not better, since the law went on the books. The law is rarely adhered to. And because the law supercedes state laws, some of which were far tougher, it has helped keep spammers in business.

So when the prosecution makes its big splash, turn a cold eye on it, and to understand why it’s happening, remember the advice of Woodward and Bernstein when they cracked the Watergate scandal: “Follow the money.”