Group questions state site-blocking law

A civil liberties group again tries to gain access to a secret list to see if Pennsylvania's attempt to block access to child-pornography Web sites affects innocuous sites.

Declan McCullagh Former Senior Writer
Declan McCullagh is the chief political correspondent for CNET. You can e-mail him or follow him on Twitter as declanm. Declan previously was a reporter for Time and the Washington bureau chief for Wired and wrote the Taking Liberties section and Other People's Money column for CBS News' Web site.
Declan McCullagh
3 min read
A civil liberties group is again trying to gain access to a secret list to determine if Pennsylvania's attempt to block access to child-pornography Web sites is affecting innocuous sites.

On Tuesday, the Washington-based Center for Democracy and Technology (CDT) appealed the Pennsylvania attorney general's recent decision not to disclose the list of Internet Protocol (IP) addresses to sites suspected of featuring child pornography. CDT is seeking the list because it suspects the government's campaign is overly broad and has forced Internet service providers (ISPs) to cordon off unoffending sites as well.

"We're trying to determine what other sites have been implicated by this law that have nothing to do with the intent of this law," said Ari Schwartz, a lawyer at CDT, which filed its request under a state open-government law. "We want the IP address to find out how many sites unrelated to the site that is meant to be blocked are also being blocked."

A Pennsylvania state law that took effect last year permits the attorney general to order ISPs to block access to Web sites suspected of featuring child pornography.

As the result of such an order from Pennsylvania Attorney General Mike Fisher, WorldCom said in September that it would block customer access to some offshore Web sites.

But some say the technique that's used to block sites is problematic. It prohibits access by making specific IP addresses off limits. IP addresses are the numeric locators, such as, that computers understand, whereas easy-to-remember domain names such as Amazon.com are what most people use to navigate the Web.

A study released in February by Harvard Law School's Berkman Center for Internet & Society concluded that because modern Web standards permit thousands of domain names to share one Internet address, blocking illegal sites tends to lead to innocuous ones being targeted as well. It said the practice of Web sites sharing IP addresses is so commonplace that Yahoo hosts 74,000 Web sites at one address and Tucows.com uses one address for 68,000 domains.

In addition to that problem, backbone provider WorldCom said that because it doesn't have the technical ability to stop residents of only one state from viewing specific Web sites, it would block the sites for all of its North American subscribers.

Fisher's office has sent 313 secret blocking notices to ISPs as of April 1 and has refused to disclose the addresses of the allegedly illegal sites, saying such disclosure would make illegal images accessible. A redacted version of a Dec. 18, 2002, letter to AOL that Fisher released tells the company to "disable access to those items identified as child pornography to your subscribers to your service...within five business days of receipt of this notice."

A spokesman for Fisher did not immediately respond to a request for comment.

Sean Connolly, a spokesman for the Pennsylvania attorney general's office, said in an interview earlier this year that the state's law "has been very successful" and has led to few complaints. "We've worked with Web hosting companies and ISPs to ensure that the illegal and offensive material is taken down and not any legal sites that may share that space," Connolly said.

No other state appears to have enacted the same sort of law, and it has not been tested in court. The list of ISPs being contacted by Pennsylvania includes EarthLink, Microsoft's MSN, Terra Lycos, Verizon, and Comcast Communications.

If CDT's administrative appeal is denied, it has the option to sue in state court. The group said it has not made that decision yet.