internetcensorship061208Internet filters are software that prevents users of a computer from accessing certain websites. They are predominantly used to block content considered inappropriate for specific users. Filters are widely used on public library and school computers. The problem with filters is that many block access to content of legitimate interest to users, but which touches upon disfavored or controversial viewpoints on issues ranging from sexuality to marijuana to paganism. This means that users are often only able to access one side of important policy and ethical debates.

Internet filters can be installed by anyone who maintains a wireless network. Parents can use them to restrict their children’s internet access, and businesses can use them to prevent their employees from being distracted at work. NCAC is most concerned with internet filters in public libraries and schools.

Filters in Public Libraries

The 2001 Child Internet Protection Act requires all public libraries that receive federal funding to install filters that block “sexually explicit” content. The American Library Association strongly opposes the Act, as does NCAC, and provides advice for libraries and their users on how to maximize internet freedom. It is important to note that adults have a legal right to ask a librarian to have the filters removed without providing a reason. Minors can request removal of the filters as well.


Filters in Public Schools

In schools, besides blocking search engine results, filters can be used to block access to social media sites such as Facebook, Twitter, and YouTube. Although these filters are implemented in order to prevent students from goofing off, they prevent students from accessing important resources such as newsworthy Facebook posts and tweets, educational videos,

Adults have a legal right to ask a librarian to have the filters removed without providing a reason.

information about alternative sexuality, and (in the case of students researching social media itself) sociological information.


Problems with Filters

Technological shortcomings:

Underblocks—The primary target of internet filters is pornography. However, filters often do not prevent users from accessing sexually explicit content. In one particularly infamous incident, a filtering service failed to block access to Pornhub. Filters frequently do not block sexually explicit thumbnails that can be expanded to full size; users can bypass a filter and access pornography by expanding thumbnails in Google searches.

Overblocks—Of far greater concern is filters’ tendency to block perfectly innocuous and valuable educational material. Because filters rely on keywords to block inappropriate material, any websites that contain those words might be blocked. Filters designed to target the word “breast” have blocked access to information about breast cancer and chicken breasts, and those that target “dick” have blocked access to former House Majority Leader Dick Armey’s website. Keyword filtering also frequently prevents users from accessing scientific information, news articles, and museum websites.

Proponents of filters want to prevent children from exposure to “explicit” materials on the internet. While this may be a worthy goal—a middle schooler watching porn in the school library may cause significant educational disruptions—filters simply do not work as intended. Because of overblocks, filters accidentally prevent students and library visitors from learning about important issues from non-explicit websites. Underblocks mean that web users can still frequently access “inappropriate” material.

Censorship: schools blocking sites that are of educational value

In addition to the inadvertent overblocks that occur as a result of keyword filtering, filters can be used to intentionally limit students’ access  materials of educational value because the viewpoint expressed is disagreeable to school officials. For instance, school districts in Tennessee were the subject of a 2009 lawsuit by the ACLU because they blocked pro-LGBT sites while allowing access to gay conversion therapy. The schools censored one side of an important moral and policy debate, preventing students from learning about important social issues. It is not unreasonable to presume that schools would use similar tactics to block student access to other disfavored viewpoints such as climate change denial and information about Islam.

Disproportionate effect on LGBT teens and economically disadvantaged groups

Filters affect anyone whom they prevent from freely browsing the internet. However, filters pose particular

Filters pose particular problems for LGBT teenagers

problems for LGBT teenagers who are struggling with issues of sexuality, mental health, and personal identity. Library and school administrators who believe discussions of LGBT issues are “sexually explicit” employ filters that prevent teenagers from accessing important resources and imply that their sexual identities are subject to condemnation and suppression. The ACLU maintains a collection of reports on this issue.

Filters also discriminate against the poor. Many households rely on school-loaned as their sole source of internet access. Therefore the censoring effect of school and library filters is amplified. Furthermore, many adults who do not own a computer use public library computers for important tasks like applying for jobs and seeking medical advice. Filters can prevent them from successfully completing these tasks.


What to do if your school is filtering the internet

Internet filters prevent students from freely browsing the internet. As explained on our issue page (insert link), filters frequently rely on keywords to block inappropriate material. Unfortunately, this enables overblocks—the inadvertent censoring of innocuous educational material. For instance, if a filter designed to target the word “breast” blocks access to a website on breast cancer, it is overblocking. Similarly, a filter that is blocking access to a museum website or news outlet is probably also overblocking due to the presence of a targeted keyword in an article on the page.

Some school administrators also use filters to censor disfavored viewpoints such as websites that help LGBT teens with issues of sexuality.

If your school has internet filters that are preventing you from accessing educationally valuable materials, here is what you can do:

  1. Identify the problem. Are you the victim of an overblock or the censorship of disfavored viewpoints?

If you are trying to access materials on non-controversial subjects (e.g. breast cancer) access educationally valuable material (e.g. an art museum’s image files, reports of the war in Syria), your filter is probably overblocking.

-If you are trying to access materials on controversial issues like sexuality or marijuana policy your filter might be censoring a disfavored viewpoint.

  1. Try accessing similar websites. If possible, try to locate the same information elsewhere. Internet filters are far from perfect. Sometimes they will block one website about marijuana policy but let you on a very similar site. If this is the case, the filter is likely overblocking. But if the filter is blocking most or all websites on marijuana policy, there may be censorship.


  1. Talk to your teacher or librarian. Do you still need or want to access a blocked website? Sometimes, teachers or librarians can bypass the filters for you or temporarily turn them off. Politely ask for access to the blocked website. When you do so, be sure to explain the following:

-Why you need to access the page. Is it for a homework assignment or paper? Do you simply want to learn about something you think is interesting? If you need medical or psychological advice from a blocked page, you should consider talking to a school nurse or counselor instead.

-Why you think the page is educationally valuable. If the page is obviously educational in nature (e.g. a museum, a scientific website, anything in the .edu domain), point this out. If not, explain to the teacher or librarian how you think the information on the page will help you do your homework or learn more about your interests.

-What you think is the problem with the filter. Teachers and librarians are usually very reasonable people who love to help students learn. If you tell them that you think the filter is overblocking, they will realize there is a technological mistake and will probably try to help you.

  1. Still no luck? Get outside help. If the filter is censoring disfavored views, teachers and librarians might be unwilling or unable to bypass the filter for you. Try contacting your local chapter of the American Civil Liberties Union. It can determine whether you have any legal recourse. The Electronic Frontier Foundation also has expertise in this area. You should also contact us. While we cannot offer you formal legal advice, we can help you understand your rights under the law. We also frequently write to school officials and use policy recommendations and public opinion to help them adopt anti-censorship policies.


Read NCAC’s previous (outdated) Internet Filters resource from 2001