"We will support the work of third parties in running education and deterrence campaigns on our platforms and are already actively engaged in discussions with CEOP and others about their proposals," a Yahoo representative said via email.
"Microsoft will support education and deterrence campaigns to target those seeking to access indecent and illegal images of children," a Microsoft representative said in an emailed statement. "Our PhotoDNA technology is already widely used across the industry to help prevent the proliferation of known illegal images and we remain completely committed to helping tackle the scourge of online child abuse content."
The Open Rights Group (ORG), an U.K.-based digital rights watchdog organization doesn't believe that banning certain search terms would be an effective approach.
"Most child abuse images are circulated in private networks, or are sold by criminal gangs," said ORG Executive Director Jim Killock in a blog post Sunday. "Banning search terms seems unlikely to combat the serious activity, which is independent of search engines."
Furthermore, even if some identifiable search terms would indeed bring up illegal images, banning those terms will likely lead to people looking for such content inventing new terms to find it, Killock said.
"Cameron invites a game of cat and mouse which is likely to have very limited impact," he said. "The terms used may hide themselves into search terms that cannot be banned because they are innocuous."
Such a ban might also affect the ability of organizations like the Internet Watch Foundation (IWF) to identify child abuse images using search engines and report them to the proper authorities, Killock said.
Cameron said in his speech that search engine providers already block abusive images reported by the IWF, but mentioned that the organization is too small to identify all of them because it relies almost entirely on members of the public reporting abusive content they've seen online.
The IWF did not immediately respond to a request for comment on whether such a ban would impact its ability to identify child abuse images.
"Cameron's announcement is symptomatic of the way the Internet is viewed and treated by policy makers," Killock said. "The technical challenges and consequences of policies are viewed as less important than the moral purpose justifying calls for action."
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