Olivier is a Professor of Law at Fordham University. His research is on information and communications law and policy. His most recent work is on the regulation of consumer-facing online services like social media, commercial surveillance, and artificial intelligence. His recent book, Reclaiming the Internet: How Big Tech Took Control—and How We Can Take It Back, came out in March 2026. The National Science Foundation and the John S. and James L. Knight Foundation have awarded him grants to support this work. He was a Senior Advisor to the Chair of the Federal Trade Commission from 2021 to 2023. He was a Senior Policy Research Fellow at Columbia University's Knight First Amendment Institute.

Olivier is on the Council for Responsible Media, as well as a member of the Advisory Board of the Tech Justice Law Project and the Academic Advisory Board of the Open Markets Institute. He has served on a variety of boards, including the ACLU of New York and the Future of Privacy Forum. Before entering academia, Olivier was a Karpatkin Fellow in the National Legal Office of the American Civil Liberties Union in New York City and a litigation associate at Jenner & Block, LLC, in Washington, D.C.