Despite the fact that such filtering systems often are hit-or-miss when it comes to blocking explicit websites, Constant said, “a seat belt won't save your life in every situation, but it will 98 percent of the time.”
City Council has asked librarians to research various filtering systems, the cost to the city, and how filtering certain websites might infringe of 1st Amendment rights or free speech.
The city of San Jose rejected Internet filtering in its libraries 10 years ago, despite its acceptance by Santa Clara County, which is where San Jose is located, in the heart of Silicone Valley.
When San Jose rejected the idea of installing filtering systems on public-use computers owned by the city, it cited potential violation of free speech rights and ineffective blocking systems. In Santa Clara, the county’s current filtering contractor is Secure Computing of San Jose for its SmartFilter screening software at a cost of $39.60 for each of the 361 public terminals, or a total of $14,295.60 annually.
However, San Jose-based Christian community standards group Values Advocacy Council President Larry Pegram said he opposes the county model because it requires filters only in children's areas. The filters can also be turned off and children can access computers in the adult areas.
Pegram said that he prefers the system employed by the Phoenix, Ariz., libraries, which uses age verification by checking the users’ library card. The system blocks all pornographic content as well as other sites deemed unsuitable for underage viewers. Users must ask a librarian if they wish to have a site unblocked for the day.
In any case, many critics say that current filtering technologies are too crude to selectively block images or keywords that may or may not be illicit, depending on the context.
The most commonly used systems use a categorized database system, developed by Secure Computing, which groups web addresses and allows the customer to choose what type of content will be blocked. There are more than 22 million sites in the database, and it is updated several times daily.
But advances in screening technologies that can differentiate between an adult website page and a legitimate site with sexual imagery are slow in development. Filters often cannot tell the difference between a breast cancer screening website or a picture of Paris Hilton with no panties on.
“It's not a foolproof system,” Santa Clara County librarian Melinda Cervantes said. “Filters have their holes. What some individuals might find offensive others may not. It's been going on long before computers came into our libraries.”
