On October 17, 2019, the Justice Collaboratory and the Solomon Center for Health Law and Policy co-sponsored a debate about the relationship between cannabis use, mental illness, and violence. The event featured Alex Berenson, author and a former New York Times reporter, and Dr. Peter Grinspoon, a primary care physician at Massachusetts General Hospital and instructor at Harvard Medical School. Berenson’s controversial 2019 book Tell Your Children: The Truth about Marijuana, Mental Illness and Violence, and its argument that that cannabis significantly increases a long-term user’s risk for developing psychosis and raises their risk for committing violent acts, provided the starting point for the debate and elicited a full-throated refutation from Dr. Grinspoon. The discussion was moderated by Professor Jason Schwartz, Assistant Professor in the Department of Health Policy and Management at the Yale School of Public Health.