Filtering Foibles

The effectiveness of filtering software has been questionable. Filtering software can operate in several ways. Examples of screening techniques include keyword blocking, approved and disapproved site lists, and labeling and rating systems. The Internet Content Rating Association implements a system in which publishers can assign labels to their websites thus rating its content, similar to the movie rating system that we are familiar with.

The performance of filtering software has been reported to be both overzealous and deficient. Overblocking occurs when websites are unintentionally blocked. This is of special concern to individuals who may be searching for special health-related information. Sites that include information on topics such as HIV, depression, and sexual health are inadvertently blocked. According to a report conducted by The Kaiser Foundation, filters that were set at the most restrictive settings blocked 24% of general health care sites and 50% of sexual health sites. The Kaiser study also revealed that at the least restrictive settings, filtering software failed to block 13% of unwanted material. A more recent 2005 study, conducted by Consumer Reports, reveals that although filtering software is improving, the best filters that intercept porn sites also blocked sites related to health, sex education, drug education and politics. Furthermore, several sites were impervious to the filtering. These included sites that depict hate, violence, illegal drug use, and weapons-making. This is called underblocking, and occurs when objectionable material penetrates the filters.