Although a New York City lawyer with Chutzpah, in court Gould would sometimes wear a tweed sports coat with patches and usually had a professorial manner relying on his cross-examination skills. Taking a lesson from Kaufman he would end the trial day by going home to dinner leaving his assisting attorneys to work up the examination for the next day.
In 1964 Gould led his law firm into a merger with the firm of his former high school classmate William Shea a politically powerful lawyer who brought the New York Mets and Shea Stadium to New York. The firm would become Shea & Gould, a very successful law firm that grew to 350 lawyers.
Gould represented such clients as Aristotle Onassis, New York City Mayor Abraham Beame and the Reverend Sun Myung Moon
In 1971-1972 Gould returned to the Cornell Law School to serve as a professor of trial advocacy and trained a new cadre of trial lawyers.
In 1979 Gould published "The Witness Who Spoke With God and Other Tales From The Courthouse" (Viking, 1979), a book of a collection of his stories which had previously appeared in the New York Law Journal.
In 1984 Gould tried one of his most famous cases representing former Israeli defense minister Ariel Sharon in his libel case against against Time Magazine for an article that included a paragraph that Sharon had urged the Phalangists to avenge Gemayel's death by the massacre that occurred on the following day. The case was tried in the same Courthouse as another libel trial was occurring in an action brought by General William Westmoreland against CBS. Both cases were widely reported on by the media. The Sharon case resulted in victory for Gould in a jury verdict for Sharon who was vindicated. The Sharon and Westmoreland libel cases were the subject of Renata Adler's book "Reckless Disregard" (1986).
In 1985 Gould's book "A Cast of Hawks" (Copley,1985) was published which dealt with the background of the United States Supreme Court case In re Neagle that he termed "A Rowdy Tale of Scandal and Power Politics in Early San Francisco" from the gold rush of 1849, the debate in California about being a slave holding state in the 1850s and the wild west until the end of the century. David Neagle had been the marshal in Tombstone at the time the shoot-out at the OK Corral and was acting as a Federal Marshal protecting U.S. Supreme Court Justice Stephen Field when Neagle killed the sworn enemy of Field, former California Justice David Terry after he accosted and threatened Justice Field. The U.S. Supreme Court held that the killing was in the scope of the Federal official's duties.