Marshall Buck attended Ohio University. He then entered the U.S. Army where he became a Captain in the Special Forces. After military service, he attended Ohio Northern University and began his practice in Youngstown, Ohio in 1980.

He is a member of the Mahoning County, Ohio State and American Bar Associations. He is active in civic and community activities, coaching youth baseball and soccer and has been elected as a permanent member of the Board of Trustees of the Canfield Baseball Club. He is a member of the Defense Research Institute.

Marshall Buck maintains a practice in the areas of defense of Medical and Legal Malpractice, Civil Rights and Municipal Litigation, Corporate, Commercial and Civil Litigation.