Professor Holmes earned an A.B. in government from Cornell in 1967 and a J.D. from Harvard in 1971. He joined the law school in 1997. Professor Holmes was executive director of the Newark Housing Development and Rehabilitation Corporation from 1971-1974, then served as assistant commissioner of the New Jersey Department of Community Affairs and later as acting commissioner. From 1979 to 1987, he was chief executive of the Newark Watershed Conservation and Development Corp., where he supervised the management and planning of the 35,000-acre Newark Pequannock Watershed. In 1987, Professor Holmes became a partner with Wilentz Goldman & Spitzer, PC, where he practiced corporate transactions, real estate and development, sports and entertainment law, and municipal law. In 1995, he became counsel to Medvin & Elberg in Newark.

A former member of the New Jersey Supreme Court Disciplinary Review Board and former president of the New Jersey Public Policy Research Institute, Professor Holmes is a board member of the Public Interest Law Center of New Jersey, a board member and secretary of Legal Services of New Jersey, a board member of Minority Athletes Networking, and a member of the board of trustees of the Victoria Foundation.