He worries some programs harm the free speech rights of users by blocking too many sites that aren't really violent or pornographic. But some software companies say revealing such information would amount to giving up a trade secret.
"When you look at the details of what the programs actually block, there's a troubling systematic trend in the systems blocking more than just porn," said Edelman, who will attend Harvard Law School this fall.
Edelman is now at the center of a suit filed Thursday by the American Civil Liberties Union in Boston federal court seeking permission for him to conduct such research and challenging a controversial 1998 law that forbids the dissemination of information that could be used to bypass copy-protection schemes.
The suit is a new way of attacking a law that has been upheld by courts in other contexts.
"The real debate going on here is less about filtering programs and more about an act that wants to regulate the production of circumvention tools that one day could be used against an e-book or music," said Jonathan Zittrain, a Harvard Law School copyright law expert who has worked with Edelman but is not involved in the case.
Edelman had asked a Seattle company called N2H2 for a list of sites that would be blocked by its software, but was rebuffed.
"Mr. Edelman's proposed research, which should be fully protected by the First Amendment, puts him at risk of liability under the DMCA," as well as a previous federal copyright act, state law and a nonnegotiable license with N2H2, the suit states.
Under the "fair use" principle of copyright law, the ACLU says, researchers should be able to analyze, discuss and criticize copyrighted work without fear or prosecution, especially when it concerns a product used at public schools and libraries.
David Burt, a spokesman for N2H2, said the company had not reviewed the suit and had no immediate comment.
The software industry says the copyright protections are essential to protect trade secrets.
"We support the DMCA," said Jeri Clausing, a spokeswoman for the Business Software Alliance. "It's been through a lot of court tests. We'll be following the newest case closely."
The DMCA has been at the center of suits involving software to "decode" DVDs and download music from the Internet.
Earlier this month in New York, magazine and Web site publisher Eric Corley agreed to drop a case over decrypting and copying DVDs that was tied to the law after losing a U.S. Supreme Court ruling.
The DMCA has been used to prosecute a Russian programmer who released a program that disabled protections in Adobe Systems Inc.'s e-book software. Dmitry Sklyarov reached a deal under which he must give a deposition and possibly testify for the government in another case.
Edward Felten, a Princeton University professor who has examined anti-piracy technology, has made a request similar to Edelman's for court permission to talk about his research in the field.
But now the ACLU is trying a new angle, arguing parents and the governments who purchase such software are entitled to know about the products they buy -- some filtering software companies do make such information available.
"Current copyright law and blocking software licenses prevent consumers from looking under the hood of the blocking products they buy," said Ann Beeson of the ACLU. "These products do not work as advertised, and consumers have a right to know they're really buying."
Copyright 2002. Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
