These findings are robust to a different measure of political freedom and the inclusion of a variety of statistical controls. In countries coded as “free,” the percentage of users visiting Onion/Hidden Services as a proportion of total daily Tor use is nearly twice as much or ∼7.8%.

In particular, the average rate of likely malicious use of Tor in our data for countries coded by Freedom House as “not free” is just 4.8%. With this important caveat in mind, our data also show that the distribution of potentially harmful and beneficial uses is uneven, clustering predominantly in politically free regimes. However, substantial evidence has shown that the preponderance of Onion/Hidden Services traffic connects to illicit sites ( 7). To be sure, there some socially beneficial content on Onion/Hidden Services and plenty of troubling content on the Clear Web. On an average day during our sample period, for example, about 6.7% of Tor network clients globally use the network to connect to “Onion/Hidden Services” that are predominantly used for illicit and illegal activities, such as buying drugs, distributing malware, or consuming and sharing child abuse imagery content. Our data show that in net terms, only a small fraction of Tor users employ the anonymity system for likely malicious purposes. In the case of the Tor anonymity network, our data provide clear, if probabilistic, answers to these questions. Others emphasize its socially beneficial potential as a privacy-enhancing tool and censorship circumvention technology ( 17– 22). With these diverse supply-side and demand-side functions ( 6), many point to the socially harmful uses of Tor as an anonymous platform for child abuse imagery sites ( 7, 8), illicit drug markets ( 9– 13), gun sales ( 14, 15), and potential extremist content that has shifted to the Dark Web after extensive Clear Web content moderation efforts ( 16). They can also use the Tor browser to anonymously read either these Onion/Hidden Services (i.e., sites with rendezvous points located internal to the Tor network) or to access Clear Web sites ( 1– 5). Tor users can act as publishers of content by using the network to anonymously administer Onion/Hidden Services for the use of others. * Although other similar tools exist, The Onion Router (Tor) is currently the largest anonymity network. Debate rages about the social utility of an anonymous portion of the global Internet accessible via the Tor network and colloquially known as the Dark Web ( 1).

Tor network statistics