In 1990, Sullivan began working at the Fraud Division in Washington, D.C. One year later, in 1991, Sullivan was assigned to the Presidential Protective Division. In 1996, he was made Assistant Special Agent in Charge of the Office of Protective Operations.
In 1990, Sullivan began working at the Fraud Division in Washington D.C. One year later, in 1991, he was assigned to the Presidential Protective Division. In 1996, he was appointed Assistant Special Agent in Charge of the Office of Protective Operations.