So a customer posts a negative review of your business that you think is not only unfair but – given the lightening speed at which word spreads on Facebook, Yelp, and Twitter – could seriously damage to your reputation.  Should you sue?

Kalamazoo, Michigan's T&J Towing decided the answer was yes. The company is suing Justin Kurtz, a Western Michigan University student who formed the "Kalamazoo Residents against T&J Towing" group on Facebook, asking for $750,000 in damages. It has also requested a court order that Kurtz "immediately cease and desist any further libellous and slanderous written claims."

Kurtz's inspiration for his group: The company towed Kurtz's Saturn SL2 in February from the apartment complex where he lives. Kurtz claims the car was legally parked and he had the appropriate parking sticker – but when he retrieved the car the sticker was scraped off and the front end of his car was damaged.  (Watch this interview with Justin Kurtz.)

What's more, Kurtz says on his Facebook page that he believes his car was broken into, and his parking sticker removed so that his car could be towed. "It is my firm belief that my car was recently 'broken into' but all that was stolen was my arboretums parking pass," Kurtz wrote. "This was an act by T&J so that they could charge me $120 to get my car out of impound." Other messages on the page allege similar misdeeds. (The Better Business Bureau of Western Michigan has awarded T&J Towing an "F" rating, and a report on the company shows a pattern of "complaints in which consumers allege the company towed vehicles in error when either the vehicle had the required parking pass, or the vehicle was not parked in a designated no parking area." The company has not responded to 17 of 20 complaints filed against it in the past 3 years, the bureau says.)

In a two-page complaint filed April 5 on behalf of T&J Towing president Joseph Bird, the company alleges Kurtz is using the Facebook group in a 'crusade to post verbal and written claims ... with allegations that are untrue and/or dishonest and without merit' and that a 'continual onslaught of libelous and slanderous claims' is losing the company business.

You may want to consider T&J Towing's a cautionary tale: The lawsuit has only fanned the flames. As news of it spread (in the Kalamazoo Gazette, but especially over Facebook and other social media networks), Kurtz's group swelled to more than 10,000 members as of Wednesday morning. Supporters are using every weapon in a consumer's arsenal, posting fake reviews on Google Maps. And consider this sample comment on Digg from bobhopeisgod: "Hahahaha! I wonder if T&J Towing are going to sue Google next for the horrible reviews people are giving them due to this law suit."  The comment had 183 diggs.

T&J Towing directed inquiries to the company's lawyer, Richard K. Burnham. He was not immediately available for comment; his secretary said he would be in court most of the day.

T&J Towing has a tough case, experts say, since the law requires it to prove Kurtz knowingly stated a falsehood. (The standard of libel is so hard to meet in the U.S. that bills to stop "libel tourism" – lawsuits brought overseas for online libel cases – have twice been introduced in Congress.)

"[T&J Towing President Bird]'s got an awfully hard lawsuit to win here," Curt Benson, a professor at Michigan's Cooley Law School, told the local TV station. He noted that the figure cited for damages was high (normally a number isn't specified).   (Bird's isn't the first company owner to take action against comments on social media – other companies have done so, mostly unsuccessfully, for comments arguably tamer than those about T&J Towing. In January an Illinois state court dismissed a suit from Chicago's Horizon Realty Group against a tenant who complained by tweet that her apartment was moldy.)

If your business is being attacked by a disgruntled customer online, consider this advice about standard operating procedure from Benson: First, ask your lawyer to write a letter asking the poster to retract the comments. Then prepare yourself and hit refresh on Facebook – the letter may well end up posted there.