Senate Structure and Operations Committee

Susan Witte is a social worker and Professor at the School of Social Work, where she teaches courses in the clinical and advanced generalist methods of the master’s program, as well as in the doctoral program. In 2019, Dr. Witte was selected as a member of the inaugural cohort of the Provost’s Senior Faculty Teaching Scholars in recognition of her outstanding achievements in both teaching and research. Dr. Witte’s research and teaching involve prevention and treating HIV/AIDS, other STIs, intimate and gender-based violence, alcohol and drug use, and related social determinants of health and mental health.

Sen. Serena Ng joined Columbia in 2007 and is the Edwin W. Rickert Professor of Economics. Dr. Ng's research focuses on empirical methods for economic data and she is managing editor of the Journal of Econometrics. She is a fellow of the Econometric Society and the International Association of Applied Econometrics. Dr. Ng has served on the Promotions and Tenure Committee (PTC), the Tenure and Review Advisory Committee (TRAC), the Advisory Committee on Conflict of Interest, the PPC subcommittee on recruitment, and various search committees. She is an affiliated member of the  Department of Statistics.

Sen. Janie Weiss is IT Manager of the Irving Comprehensive Cancer Center, a role she has held for over 30 years. She assists faculty, staff, and students with their IT needs, helping to advance the research enterprise. On the University Senate, Janie serves on the Rules Committee, Structure and Operations Committee, Commission on the Status of Women, and Commission on Benefits.

Sen. Jackie Dugard (BA, MPhil, PhD, LLB, LLM) is a Senior Lecturer at the Institute for the Study of Human Rights (ISHR), where she is the outgoing Director of Graduate Studies for the Human Rights Studies MA (HRSMA) program. Prior to joining Columbia in July 2022, she was an Associate Professor of Law at the University of the Witwatersrand (Wits) in South Africa (2014-2022), where she is now a Visiting Professor of Law. With a background in law and social sciences, Jackie has published widely on social- and climate-justice. She is a Global Fellow at the Centre on Law & Social Transformation (University of Bergen, Norway), and an editor of the South African Journal on Human Rights.
Jackie has significant leadership experience - she was a co-founder and the first Executive Director of the non-governmental organization, Socio-Economic Rights Institute of South Africa (SERI), and the founding first Director of the Gender Equity Office (GEO) at Wits. As a human rights academic and practitioner, she is committed to governance accountability and improving the working conditions of non-tenure track faculty, as evident in her involvement in the organizing committee for the Contingent Faculty of Columbia University (CFCU-UAW)  unionization process currently underway for non-tenure track colleagues. 

Sen. Henry Ginsberg is the Irving Professor of Medicine at the Vagelos College of Physicians and Surgeons, where he has conducted basic and translational research on lipid metabolism and cardiovascular disease for 37 years. Dr. Ginsberg was Director of the Irving Center for Clinical Research from 1994 to 2006 and the Irving Institute for Clinical and Translational Research from 2006 to 2017. From 1992 to 2008 and from 2014 until the present, he has been PI on an NHLBI T32 postdoctoral training program in Arteriosclerosis Research. Dr. Ginsberg has published over 400 peer-reviewed and invited papers in journals, and has received funding from the NIH for more than 40 years. He also sees patients with severe lipid disorders and teach. On the University Senate, he serves on the Commission on the Status of Women and on the Structure and Operations Committee, and hopes that his many years on the faculty allow him to offer insights and perspectives relevant to the issues facing the University.

Sen. Henning Schulzrinne is the Julian Clarence Levi Professor of Mathematical Methods and Computer Science and Professor of Electrical Engineering. On the University Senate, he serves on the Executive Committee and on the External Relations and Research Policy and Structure and Operations committees.

Professor Schulzrinne received his Ph.D. from the University of Massachusetts in Amherst, Massachusetts. He served as Chair of the Department of Computer Science from 2004 to 2009 and as Engineering Fellow, Technical Advisor, and Chief Technology Officer of the Federal Communications Commission (FCC) from 2010 until 2017.

Professor Schulzrinne has co-developed a number of protocol standards that are now used by almost all Internet telephony and multimedia applications, including RTP, RTSP and SIP. He is a Fellow of the Association for Computing Machinery (ACM) and the Institution of Electrical and Electronics Engineers (IEEE).

Sen. Greg Freyer is Professor and Faculty Director of Graduate Education in the Department of Environmental Health Sciences at the Mailman School of Public Health.  He directs the DrPH and MS Toxicology programs and the Certificate in Toxicology. Dr. Freyer has been a member of the University Senate since 2011. He co-chairs the Faculty Affairs, Academic Freedom and Tenure Committee and serves on the Budget Committee, Structure and Operations Committee, the Commission on Benefits and the Commission on the Status of Health Sciences.

Dr. Freyer is deeply engaged in developing educational programs, teaches multiple courses and was recipient of both the Mailman School of Public Health Excellence in Teaching Award and the Columbia University Presidential Teaching Award in 2014. Dr. Freyer’s research has focused on cellular responses to environmental insults, particularly related to DNA damage. 

Sen. Daniel Wolf Savin is Senior Research Scientist in the Columbia Astrophysics Laboratory. Dr. Savin's work addresses cutting-edge questions in astrophysics, planetary science, and solar physics through observations coupled with laboratory astrophysics studies in atomic, molecular, condensed matter, and plasma physics. On the University Senate, he represents Professional Research Officers and chairs the Research Officers Committee. He serves on the Executive Committee, co-chairs the Structure and Operations Committee, and serves on the Budget Committee. Dr. Savin is a Fellow of the American Association for the Advancement of Science, the American Astronomical Society, and the American Physical Society. In 2026 Dr. Savin was awarded the Laboratory Astrophysics Prize of the Laboratory Astrophysics Division of the American Astronomical Society.

Sen. Dafne Sarfati is a senior at the Fu Foundation School of Engineering and Applied Science, studying industrial engineering with minors in computer science and entrepreneurship and innovation. Originally from Istanbul, Turkey, she is passionate about utilizing technology, data analytics, and entrepreneurship to drive social innovation, sustainability, and educational equity. 

Dafne has served on the Engineering Student Council for two years as the International Student Representative, where she advocated for policies and initiatives that support the academic, career, and campus life of international students. She is currently the Co-President of the Columbia Turkish Students Association and the Treasurer for the Columbia Organization of Rising Entrepreneurs (CORE), where she manages club finances and leads weekly workshops on entrepreneurship and product management. She is also involved with Columbia Undergraduate Admissions, serving on the Engineering and Global Recruitment Committees. 

Dafne has worked on projects such as developing a community-led well-being index in New York City, and creating a digital course advising system for Columbia’s Industrial Engineering and Operations Research Department. Through the University Senate, Dafne hopes to advocate for international students, promote transparency, and strengthen communication between SEAS undergraduates, the University Senate, and the wider Columbia community.

Brendan O’Flaherty is Professor of Economics. On the University Senate, he serves as parliamentarian, co-chairs the Senate Structure and Operations Committee and is a member of the Elections Commission.

Professor O'Flaherty's research focuses on homelessness, race, and the economics of cities. Before coming to Columbia in 1987, he spent two years as an aide to Kenneth Gibson, the first black mayor of Newark, N.J. He previously served as acting director of finance for the City of Newark and chaired the Program and Planning Committee of the Arts and Sciences at Columbia. He received his Ph.D. from Harvard.