Cracking the Code Of Online Filtering

Published: July 19, 2001

Correction Appended

EVERY year the Electronic Frontier Foundation hands out its Pioneer Awards to people who have played crucial roles in the history of technology. Recipients have included visionaries like Ivan Sutherland, creator of some of the first computer graphics programs; Douglas C. Engelbart, an inventor of the mouse; and Linus Torvalds, inventor of the popular Linux operating system.

This year one of the three winners was Seth Finkelstein, an activist who decrypts filtering programs, the software used by private companies, libraries and schools to block out undesirable sites. As a founder of the Censorware Project, an anti-filtering advocacy group, Mr. Finkelstein has influenced public debate and legal decisions, including a First Amendment case on filtering policy at a public library in Virginia.

But most people have probably never heard of him, and until recently that is the way Mr. Finkelstein, a reclusive 36-year-old computer programmer, wanted it. Over the last six years he has spent hundreds of hours decrypting the blacklists of popular Web filtering programs like Cyber Patrol and X-Gear.

Most filters work by sending out programs that comb the Web for banned words and then produce a list of Web sites containing those words. Those sites are compiled into the closely guarded blacklists that Mr. Finkelstein tries to uncover.

But don't call him a hacker. He gets prickly when he hears that word. Instead he describes himself as a civil-libertarian software engineer.

Mr. Finkelstein contends that filtering is not only inherently flawed but that in many cases it even acts as a deliberate censor. Many of the Web sites on the blacklists -- feminist sites, gay and lesbian information sites, health sites and religious sites -- are more political than pornographic in nature. ''This is inevitable,'' Mr. Finkelstein said. ''Once you give censors free rein, they go after sex. They go after sex education. They go after feminism. They go after gay rights.''

The makers of filtering software say that criticism of their products' accuracy is old news and they are addressing the problems. ''Technology evolves,'' said Susan Getgood, vice president for home and education markets at SurfControl, a maker of Web and e-mail filtering products. ''It is a long way from the Model T to the BMW Z3 and a long way from the early days of filtering to the products on the market today.''

Correction: August 8, 2001, Wednesday An article in Circuits on July 19 about a computer programmer's efforts to decode Internet filtering software misidentified one set of programs used by companies, schools or libraries to block access to disapproved Web sites. They are called X-Stop, not X-Gear.