Why Did Craigslist Cave?

Why did Craigslist bow to law enforcement pressure and agree to drop its "erotic services" category (replacing it with the presumably tamer "adult services")?

It's certainly a response to the arrest this spring of Phillip Markoff, the medical student charged with killing a woman he allegedly met on Craigslist, and to the lawsuit filed earlier this year by Cook County Sheriff Tom Dart of Illinois, who alleged that the site served as a prostitution clearinghouse.

But two other events likely encouraged Craigslist's operators to act today. The attorney general of South Carolina, Henry McMaster, vowed last week to criminally charge the company if it didn't shut down its erotic services site by Friday.

And perhaps more significantly, Craigslist may fear a crack in the legal protection it enjoys against lawsuits. The ironically titled Communications Decency Act protects internet service providers like Craigslist, Yahoo and MySpace from liability that would arise from information posted on their sites. But last week a federal court made it possible for a woman to sue MySpace after it promised, then failed, to remove nude photographs her ex-boyfriend posted. Her argument – that MySpace broke an enforceable promise to her – doesn't relate to the Craigslist suits, but it sends a message that judges are looking for ways that aggrieved individuals (or Attorneys General) can hold website operators responsible when the sites make crimes or bad behavior possible.