Voor deze aanstelling was hij onderzoeksdirecteur van de International Council on Human Rights Policyin Geneve, waar zijn onderzoek zich voornamelijk richtte op milieurecht en op privacy. Ook werkte hij enige tijd als publicatie-directeur bij de Open Society Justice Initiative in New York. Hij deed onderzoek naar klimaatverandering en het Kyoto mechanisme in Dakar, Senegal.

Humphreys' huidige onderzoek richt zich op de verdeling van risico's en veiligheid onder internationaal en transnationaal recht. Hij was redacteur van het boek Human Rights and Climate Change(2009) en schreef Theatre and the Rule of Law: Transnational Legal Intervention in Theory and Practice(2010).

Stephen Humphreys holds a PhD in law from the University of Cambridge and a Masters in comparative and international law from SOAS, University of London. Prior to joining the London School of Economics as a lecturer in 2009, he was Research Director at the International Council on Human Rights Policy in Geneva, where his research focused on environmental law and on privacy and surveillance. He previously acted as publications director for the Open Society Justice Initiative in New York, and before that he oversaw a project monitoring minority rights and discrimination in ten EU accession countries for the Open Society Institute in Budapest. He conducted research on climate change and the Kyoto mechanisms with ENDA Tiers Monde in Dakar, Senegal.

Humphreys' current research focuses on the distribution of risk and security under international and transnational law. He is the editor of the book Human Rights and Climate Change (2009) and wrote Theatre of the Rule of Law: Transnational Legal Intervention in Theory and Practice (2010).