'Mad Men' flap shows why execs should listen to marketing folks before lawyering up.

When you have lawyers on retainer, it’s hard not to take their word as gospel. For decades, attorneys have been the ultimate weapons in the black-and-white world of corporate America.

These days, corporate lawyers — while in some ways more valuable than ever — can also do more harm than good. Try to squash one pest with a bigfoot tactic like a “cease and desist” order, and you’re bound to stir up a hornet’s nest that can wreck your public image.

This week’s example was the flap over characters from AMC’s hit show “Mad Men” appearing on the microblogging site Twitter.

Fans created accounts for most of the show’s characters, then carried on amusing conversations with each other and with the public. It was a harmless bit of fan-fiction, executed so well that many marketing types assumed it was part of a viral effort by AMC itself.

What happened next is still a little foggy, but the result was that several of the Mad Men character accounts were suspended. Twitter said it received a Digital Millennium Copyright Act takedown notice from AMC. The channel claims it simply wanted to discuss the issue with Twitter without destroying the accounts.

Either way, things got legal at a time when they really didn’t need to be. There was an immediate backlash on Twitter and entertainment blogs as people felt “the corporate oppressor” was taking a big whiz all over the fun.

Eventually, AMC’s marketing agency was credited with getting the accounts restored, but the damage was done. What could have been a great example of free publicity had been tainted by legal maneuvering.

So what’s to be learned here?

It’s going to become more and more common for fans to create their own extensions of shows, movies and other branded entertainment online. Should they all be allowed to live on, unfettered by intellectual property rights? No, but I do think companies need to start being far more selective in whom they target.

How can companies tell friend from foe? That’s where marketing and PR come in. Executives need to be open to both their legal department and their marketing department before unleashing the hounds. That way, if you absolutely must drop the hammer, you’ll at least be ready to explain why.