In the years since the federal government passed the 1998 law aimed at protecting children while they used the Internet, technology made the job substantially easier.
At the same time, the purveyors of pornography and other adult material have become more aggressive as they seek to reach unwitting audiences of all ages.
In their ruling Tuesday prohibiting the Justice Department from enforcing the Child Online Protection Act, five Supreme Court justices suggested that software filters could do more to shield minors from inappropriate online content than a federal law.
Internet experts generally agreed, though they said filters had a raft of shortcomings.
“It’s a cat-and-mouse game, but we’re learning faster than the bad guys,” said Andrew Weinstein, a spokesman for America Online, the country’s largest Internet access provider.
Some Internet experts said the Supreme Court wasn’t praising filters so much as faulting the law.
“It’s likely that filters have gotten better, but there are limits,” said lawyer Kevin Bankston of the Electronic Frontier Foundation, which opposed the government in a separate case over required filters at public libraries. “You will never have a judge on a [computer] chip that says, ‘This meets the legal definition of obscenity.’ ”
Michelle Collins, director of the exploited-child unit at the National Center for Missing and Exploited Children, said she was not sure parents were better off now than they were six years ago, when the Child Online Protection Act was passed.
The technology has improved, but so many more children and adults are online that there’s far more opportunity for harm.
“It’s certainly a risk for adults and kids alike,” Collins said.
Filters are far from an ideal solution, often blocking sites that are harmless.
It’s also relatively simple for a determined teenager to disable or otherwise evade the filters with free software accessible through a Web search.
Filters work best when they are set up to protect children who aren’t looking for anything offensive.
AOL, MSN and other Internet service providers offer parental controls that can be tailored by age group and an array of other preferences.
For the youngest children, some services offer a virtual sandbox of largely handpicked sites. Older children can be blocked, at least in theory, from sites devoted to sex, gambling and other vices. If a child requests access to a site that has been blocked, a parent can view and unblock it if desired.
One advantage of these services is that they work even if the child is logged on at a friend’s computer, as long as the same access provider is used.
Parents can purchase additional filters that reside on a specific computer. Software programs such as CyberSitter and CyberPatrol draw mixed reviews from parents -- instant messaging is especially tricky to control -- but are often considered better than nothing.
Filtering software combined with parental controls is the most effective technology mix, said AOL’s Weinstein, “but they are not a replacement for parental involvement.”
Even with everything installed, scourges such as spam and pop-up ads can lead to unpleasant experiences, and battling those is rarely a winning proposition.