He entered Harvard Law School, where he won the Roscoe Pound Prize for brief writing and oral argument, and graduated in 1955.
He was admitted to the New Jersey Bar the following year after a clerkship with Superior Court Judge Edward Gaulkin.
He was a New Jersey Superior Court judge from May 1971 through September 1976, when he resigned to return to private law practice.
After Kean won the recount, he announced his choice of Kimmelman as Attorney General on December 14, 1981.
A resident of the Short Hills section of Millburn Township, Kimmelman was confirmed by the New Jersey Senate and sworn in on January 19, 1982, the day of Kean's inauguration.