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Research by Andrea Forte, Nazanin Andalibi and Rachel Greenstadt

Wikipedia blocks edits from Tor — how does this affect the quality and coverage of the "encyclopedia that anyone can edit?" How do captchas and blocking of anonymity services affect the experiences of Tor users when they are trying to contribute content? What can projects do to better support contributions from people who value their privacy?

We are a group of researchers from Drexel University studying these questions. Our initial study of privacy in open collaboration projects, entitled Privacy, Anonymity, and Perceived Risk in Open Collaboration: A Study of Tor Users and Wikipedians, was recently published in advance of its presentation at the ACM conference on Computer-Supported Cooperative Work and Social Computing (CSCW) in February. Our findings offer a rare look at why people turn to privacy tools like Tor and how they experience the Internet as a result. This work was inspired by a previous Tor blog post, A call to arms: Helping Internet services accept anonymous users.

We interviewed 23 people from seven countries ranging in age from 18-41; 12 Tor users who participate in online projects and 11 Wikipedia editors who use a variety of privacy tactics. The Tor Project and Wikimedia Foundation are organizations committed to similar ideals — a free global exchange of information in which everyone is able to participate. The study's central finding is that perceived threats from other individuals, groups of people and governments are substantial enough to force users below the radar and curtail their participation in order to protect their reputation, themselves, and their families.

In nearly all interviews, participants described being wary about how aspects of their participation in open collaboration projects would compromise their privacy or safety. Many participants described crisis experiences of their own or of someone they knew as antecedent to their model of threat in online projects.

Their reasons for guarding their privacy online ranged from concerns about providers obtaining and using their browsing history for targeted advertising to actual verbal abuse, harassment and threats of violence. The most common concern voiced by participants was a fear that their online communication or activities may be accessed or logged by parties without their knowledge or consent.

This threat, which became very real for many Americans after Snowden revealed the extent of the National Security Agency's surveillance and monitoring practices, has been ever-present for users in other countries for some time. According to one non-U.S. respondent "in my country there's basically unknown surveillance going on ... and I don't know what providers to use so at some point I decided to use Tor for everything."

For a political activist, dissident, or just someone who has expressed strong political opinions the threat is multiplied. One such participant who uses Tor said "they busted [my friend's] door down and they beat the ever living crap out of him...and told him, "If you and your family want to live, then you're going to stop causing trouble." This person's privacy strategies were quickly transformed after that experience.

Eleven of the study's participants were recruited from the ranks of Wikipedia editors who expressed concerns about maintaining their privacy. In comparison to political dissent, helping to add information to Wikipedia might seem innocuous, but especially editors who work on controversial topics are also being threatened and harassed. Wikipedia allows anonymous posting, but it does not permit users to mask their IP addresses and blocks Tor users — except in special cases. So wading into the controversial territory, even to present a fact-backed, neutral point of view, puts editors at risk. Some Wikipedians described threats of rape, physical assault, and death as reprisals for their contributions to the project.

Administrators of the site, who often spend their time on managerial tasks and enforcing policies, also reported being harassed or threatened with violence. "It's a lot of emotional work," said one study participant. "I remember being like 13 and getting a lot of rape threats and death threats and that was when I was doing administrative work."

Our analysis suggests that Wikipedia and other collaborative projects are losing valuable contributions to privacy concerns. If certain voices are systematically dampened by the threat of harassment, intimidation, violence, or opportunity and reputation loss, projects like Wikipedia cannot hope to attract the diversity of contributors required to produce "the sum of all human knowledge."

In response to this problem, our research agenda aims to support communities like Wikipedia in developing tools and norms that value and welcome anonymous contributions.

For more:

Andrea Forte will be speaking at the next WikiResearch showcase which will be live-streamed this Wednesday 12/21 at 11:30am PT / 7:30pm UTC.

Read the paper: "Privacy, Anonymity, and Perceived Risk in Open Collaboration: A Study of Tor Users and Wikipedians"

Watch the video from the 32c2 talk: What is the value of anonymous communication?