Halpern is considered a pioneer in public interest law, responsible for various entrepreneurial and educational initiatives that contributed to legal, academic, social justice, and contemplative communities.
After finishing law school, Halpern clerked with Judge George T. Washington of the United States Court of Appeals for the District of Columbia Circuit.
[3] In 1969, Halpern left Arnold and Porter and co-founded one of the nation's first public interest law firms, the Center for Law and Social Policy (CLASP) in Washington D.C.[4][5] CLASP's idea of bringing the nation's emerging social movements into the courtroom was novel and much needed, and it attracted early support from legal leaders like former Supreme Court Justice Arthur Goldberg, former Attorney General Ramsey Clark, and former Secretary of the Interior Stewart Udall.
[8] Under his leadership, the foundation developed and supported many innovative philanthropic initiatives, including Healing and the Mind with Bill Moyers and the dialogues between the Dalai Lama and spiritual leaders of the American Jewish community.
[9] The foundation launched a creative program in the area of contemplative practice that supported meditation retreats to bring together, inspire, and invigorate environmentalists, social activists, and cultural intellectuals.
[13] The mindfulness initiative was built on earlier contemplative practice exploration at Berkeley Law, including the Mindful Lawyer conference,[14] which drew nearly 200 lawyers, professors, and judges to Berkeley to discuss connections between law, meditation, compassion, and justice.