John F. Kennedy Jr. served as an assistant district attorney in the office of the Manhattan District Attorney, Robert Morgenthau. This office falls within the jurisdiction of the Southern District of New York (SDNY). He was sworn in on August 21, 1989, and was assigned to prosecute political corruption. He worked there until 1993, handling cases involving white-collar crime and fraud. While he initially failed the New York bar exam twice, he passed on his third attempt in July 1990, allowing him to continue his work at the DA's office.
The SDNY is a prominent federal court and the U.S. Attorney's office that covers Manhattan and several other New York counties. It is known for handling a large number of civil and criminal cases, including white-collar crime, and has jurisdiction over the nation's largest financial institutions.