Thomas received his AB in Psychology and Islamic and Near Eastern Studies from Washington University in 2009. He conducted a senior thesis project on how reminders of historical injustice by one’s own nation affect willingness to criticize the nation. In 2008 he travelled to Tbilisi, Georgia to conduct field experiments involving memories of the Rose Revolution. After college, Thomas interned with the International Center for Journalists in Washington D.C., and he wrote news briefs for the website Palestine Note.
He is now collecting data for a longitudinal project on cross-ethnic friendship among middle schoolers. In addition, he is also interested in framings and perceptions of intergroup conflict, emotions, and public support for different forms of third-party interventions. He was previously involved in program evaluation for PROOF: Media for Social Justice; their Rescuers Project exhibition, to be shown in Bosnia and Cambodia, which will showcase examples of individuals who have intervened in times of genocide or mass violence to rescue others. Thomas O'Brien was awarded a National Science Graduate Research Fellowship in 2013 for his purposed research on the effects of social identity and social categorization on persuasion in foreign policy attitudes.