Maladaptive COPA Mechanism: Why Filters Are Better Than Laws at Keeping Kids Away From Porn

Worse, as Reed concluded based on expert testimony, none of the "age verification" options mentioned in COPA is a reliable way to verify age. The law thus would cost Web sites money, inconvenience adults, reduce readership and chill online speech without accomplishing the avowed objective of shielding minors from pornography.

Filtering software, by contrast, is easy and cheap (often free) to use, and it can be close to 100 percent effective at blocking porn, whether it originates in the United States or abroad. Even the worst-performing programs, Reed found, block around 90 percent of sexually explicit material.

While mistakenly preventing access to unobjectionable Web sites remains a problem, dynamic filtering using improved algorithms has reduced the frequency of over-blocking to as low as 5 percent, and parents can always add erroneously blocked sites to the "white list" of approved addresses. Filters can be adjusted based on the age and maturity of the child (even for several different children) and the subjects parents consider inappropriate (e.g., sex, violence, drugs, racism). Passwords prevent kids from circumventing the controls.

This kind of flexibility is impossible to achieve through legislative diktat. Filters allow parents to choose the kind of protection that best suits their values and their children. Most important, unlike laws that threaten to impose preschool propriety on everyone, they can be turned off by grownups.