Murdaugh Madden was general counsel for HSUS from 1971 until 1990, and senior counsel until his death in February 2008. He was 85.
According to his obituary, he was at the forefront of the investigation into bird abuse on the film set of Jonathan Livingston Seagull and unsuccessfully sued the Department of Defense over its plan to kill millions of blackbird pests near military facilities. He also oversaw the founding of the World Society for the Protection of Animals.
In his later years at HSUS, Madden's work concentrated on bequests to HSUS that had been contested by heirs.