No Encore for Encore? Ethical questions for web-based censorship measurement

by Arvind Narayanan and Bendert Zevenbergen

A pair of computer scientists recently developed a clever way to measure Internet filtering and censorship worldwide, including countries such as China and Iran. Their system, named Encore, does this by executing a snippet of code on the web browsers of people who visit certain web pages — without the consent of those individuals. It caused a minor furor over research ethics in the computer networking and Internet measurement research communities.

We analyze this conundrum through the lens of established ethical principles, but keeping in mind the peculiarities of Internet and big data research: its global reach, large scale, and automated nature. We also comment on the unusual model that computer scientists use for ethical oversight. We hope that the questions we raise will be useful for researchers facing similar dilemmas in their own work, as well as for students of research ethics, both in technical disciplines and in fields such as law and philosophy.