On January 1, 1975, he began a lengthy career at The Legal Aid Society,[3] serving from 1975 to 1994 as Attorney-in-Chief and Executive Director, and later as Chairman of the Board until 1998.

Murray was said to have "helped to raise the standard of the free legal advice provided for poor and indigent defendants facing criminal charges in New York City."

[5] In 2007, The Legal Aid Society announced the creation of the Archibald R. Murray Memorial Fund for Law Student Loan Forgiveness "to honor the memory of Arch Murray and celebrate his many accomplishments that helped to provide quality legal services for low-income New Yorkers.

Murray noted in the memo that nunchaku are used in karate and other martial arts training and that, "in view of the current interest and participation in these activities by many members of the public, it appears unreasonable--and perhaps even unconstitutional--to prohibit those who have a legitimate reason for possessing chuka sticks from doing so.

"[9] In October 1994, in the wake of Mayor Rudy Giuliani's decision to terminate New York City's contract with The Legal Aid Society, Murray sent a letter to the City's Corporation Counsel, Paul A. Crotty, arguing that Giuliani had no legal basis for terminating the contract.