Rosenbaum was born in New York City, in Washington Heights, and grew up in Miami Beach, Florida, where his parents moved when he was nine years old.

In Spring 2005, he was a visiting professor at the Benjamin N. Cardozo School of Law at Yeshiva University, where he has been a frequent speaker, including at the annual Yom HaShoah Lecture hosted jointly by the American Society for Yad Vashem and Cardozo's Program in Holocaust & Human Rights Studies on “Remember How the Law Went Horribly Wrong”; the 60th anniversary of the Nuremberg Trials on "A Reappraisal and Their Legacy";[3] and as the Uri & Caroline Bauer Distinguished Lecturer on Rosenbaum's book, “The Myth of Moral Justice."

Prior to teaching, he was an associate in the litigation department at Debevoise & Plimpton, where he also coordinated the firm's pro bono cases.

As a cultural commentator, Rosenbaum has been invited to speak at universities and other venues around the world, including the Yale University International Human Rights Symposium,[4] Princeton University,[5] the UCLA Center for Jewish Studies,[6] the Goethe-Institut in New York,[7] and the United States Holocaust Memorial Museum in Washington, D.C.[8] He has served as an advisor, writer, co-producer, and commentator on several documentary films, including “Imaginary Witness: Hollywood and the Holocaust," produced and directed by Daniel Anker, “Forgiveness,” directed by Helen Whitney for PBS, and “Sidney Lumet, A Moral Lens,” a PBS American Masters film.

As the moderator of the Trials & Error series at 92Y,[15] his panelists revisit high-profile court cases for a behind-the-scenes look at the legal strategies and foibles with lawyers, journalists, and the parties to the action or their family members and close associates.