But without closely examining the filtering option, users of America Online's popular chat service may be unwittingly omitting incoming words that many wouldn't associate with the Net's red-light districts.
ICQ's default setting is "filter disabled," and people can edit the list. However, the service is referring its 28 million registrants solely to the ClickChoice Company, whose DirtyWords and MoreDarnDirtyWords lists replace with asterisks not only a wide range of sexually oriented terms, but phrases such as "popculture," "lesbian," "accounting.com," "safesex," and "now.org," the home page for the National Organization for Women.
"What kind of 'click choice' is that?" said Emily Whitfield, a spokeswoman for the American Civil Liberties Union.
"The ACLU has always said that parents, not governments or corporations, should make the decision of what their children see online," she noted. "But if parents are going to use this stuff, they should check the ingredients list just as closely as they would on a box of cereal."
Like AOL's leading online access service, ICQ, which allows users to chat and send instant messages to one another, is quickly gaining market share; it also aims to let users control the type of material they receive.
AOL, for one, has been on the front lines of the Net free speech debate, which has Net providers from libraries to Disney's Go Network walking a fine line between offering child-safe content and dealing with the widely acknowledged imperfections of filtering technologies.
ICQ's content controls point users to ClickChoice through its Words Lists menu within its Security & Privacy preferences. From there users are taken to ClickChoice when they select Web Help to get access to an "objectionable" words list.
Despite ClickChoice's exclusive position in ICQ's filter section, ICQ contends that it is not promoting the list.
"We give our members choice and let them decide. We aren't going to make those editorial decisions," said ICQ spokeswoman Jeanne Meyer.
"We haven't even been promoting this feature, because we're not done with it," she added. "We are in the process of soon adding many other options for filtering, such as multilingual lists."
That filtering tools sometimes block nonsexual sites is nothing new. Still, civil liberties activists have long warned consumers to review the actual list of sites blocked by Net screening programs.
In fact, ClickChoice's list appears to be identical to one compiled by Solid Oak Software for its Net filtering program, Cybersitter. The similarity between the lists was discovered by the teen anticensorship organization Peacefire.
Solid Oak's list caused a storm of controversy almost two years ago when Peacefire's founder, Bennett Haselton, cracked it and revealed that the product blocked sites such as the International Gay and Lesbian Human Rights Commission. Cybersitter customers normally aren't able to view the list.
When contacted by CNET News.com, Solid Oak president Brian Milburn said that ClickChoice seemed to be using his company's list without permission. For example, the ClickChoice list includes the phrase "DontBuyCybersitter," a characteristic unique to Solid Oak's filtering program.
"I'm going to probably refer this to our lawyers, because they are definitely using our list--there are some sites in there that don't exist. We planted those seeds to catch illegal uses of our list," Milburn said.
A representative for ClickChoice was not sure how the list was compiled. The firm also seemed to have no idea that it had stumbled into the crossfire of an ongoing free speech debate over whether filtering tools scratch out Net content that many groups argue is not pornographic and has redeeming social value.
"We were asked by ICQ to compile a list for them, and we provided it in October. But I don't know where we sourced it, and I'm looking into it," said Joe Provissiero, ClickChoice's vice president of marketing and sales.
Although ICQ reaches millions of people, it was apparently a side job for ClickChoice. The company has a more than $5 million deal with Net Shepherd to build a real-time Internet filtering service. Net Shepherd already offers Net site filtering and rating technologies that compete with Cybersitter.
The Net Shepherd project "is our core competency," Provissiero added.
Nonetheless, free speech watchdogs say that online services such as ClickChoice and ICQ should be more conscious of the tools they are offering consumers and clearly disclose when the products go beyond blocking "dirty" words.
Net users also should better investigate the filters they install. "Otherwise they can get surprises like this," said the ACLU's Whitfield.