The Censorware Project's 61-page report examines Net surfing records obtained via Utah's Freedom of Information Act from Utah Education Net, a network for public schools and libraries that uses Secure Computing Corporation's SmartFilter to screen out adult-oriented material.
Of the more than 500,000 sites blocked by SmartFilter's proxy-based software, the Censorware Project found that in some instances the Declaration of Independence, the Koran, William Shakespeare's plays, and The Adventures of Sherlock Holmes were blocked along with sites considered obscene, violent, sexual, or "worthless."
SmartFilter, which caters primarily to about 7,000 private corporations, was not asked by the Censorware Project to reply to the report and still hasn't fully reviewed the findings, according to spokesman Ken Montgomery.
"Are we saying our software is perfect? No," Montgomery said.
The report also notes that humans haven't reviewed every site on SmartFilter's list; Montgomery conceded today that the company "may" have claimed otherwise in the past.
"Every 'contested' site is reviewed by a human being," Montgomery said. "We may have said that [all sites are reviewed by a person] at some point when the list was much smaller."
But the Censorware Project said the flaws go beyond the contested sites.
"We discovered a bunch of evidence that they don't use humans to review their sites," said the Censorware Project's Michael Sims, the lead author of the paper. "For example, a Florida State Web page was banned under SmartFilter's 'gambling' [category], but the site is not about gambling--the surname of the person who created it is 'Wager.'"
It's no secret that filtering tools sometimes block nonsexual sites or content outside their stated parameters. Just last week America Online's ICQ chat service yanked its link to a controversial list of "objectionable" words that blocked phrases that were neither pornographic nor profane.
SmartFilter noted that it is trying to keep its list of blocked sites up-to-date, though the Censorware Project pointed to examples in which it had fallen short.
For instance, the report states that SmartFilter blocks "Mormon.com." SmartFilter said that when it first reviewed Mormon.com, it was pornographic; but now it's not, and it will be removed from its list.
Secure Computing plans in a few weeks to launch SmartFilterWhere, a program that lets Web site creators find out whether their site is banned by one of the product's 27 categories and then challenge the listing.
Like many filtering firms, SmartFilter doesn't plan to make its filter list available to customers or the general public.
"The reason we do not disclose our control list is because it is the core of our product, and we can't make it available to competitors," said Gus Maldonado, product marketing manager for SmartFilter.
"We've never had requests from direct customers for the control list," he added. "They purchase it from us for the convenience of not having to do this themselves."
But groups like the Censorware Project and the American Civil Liberties Union say customers should be able to check the "ingredient list" to make informed decisions about which products to use and whether to use them at all.
"I hope that school systems that are using these products will scrutinize them," the Censorware Project's Sims said.