The latest from a federal appeals court in Chicago may make civil liberties advocates cheer, but will likely unsettle parents of children who frequent social networks: The 7th U.S. Circuit Court of Appeals ruled Wednesday that barring registered sex offenders from using Facebook and other social networks is unconstitutional.

The American Civil Liberties Union in Indiana had filed a class-action suit on behalf of a group of sex offenders, including one man who was convicted of child exploitation. The clients were no longer on probation, yet were subject to an Indiana law that prohibited their use of social networks. Last June, a U.S. district judge ruled to uphold the law, but when it reached the appeals court, the decision was overturned on the basis that it violated their right to free speech.

The ACLU made the case that, although the law was intended to protect children from online predators, barring social media sites went too far. These days, sites like Facebook are indispensable for plenty of legitimate purposes, including political, business and religious activities.

"Indiana already has a law on the books that prohibits inappropriate sexual contacts with children," including online activities, says ACLU legal director Ken Falk. "[But] this law sought to criminalize completely innocent conduct that has nothing to do with children."

The controversy may seem strange, considering Facebook technically restricts children under 13 from registering for accounts. But the rule isn't tightly enforced, as there are plenty of young users on the site, and even if it was, there's a huge userbase of perfectly sanctioned 13-to-17-year-olds on the network. This may be what has spurred states like Indiana, Louisiana and Nebraska to pass their own social media legislation for sex offenders.

A similar law in Louisiana got thrown out last year, prompting the state to pass a new revised version that merely requires sex offenders to identify themselves on social networks. And in Nebraska, a federal judge struck down parts of its law last October — specifically segments that prohibited use of sites like MySpace and Facebook and called for surveillance hardware or software to monitor computer activities. 

What do you think? Is Facebook use covered under free speech? And should sex offenders be prohibited from using social media, banned from it or monitored?