Bacon was last seen leaving for his night shift job at Behr-Manning factory (now known as Norton Co.) in Watervliet, New York at approximately 11:30 p.m. on April 10, 1969. He was supposed to pick up his brother along the way. He never picked up his brother, never arrived at work and has never been heard from again. Bacon's car was found abandoned on Oil Mill Hill, not far from the Waterford Bridge. His lunch was in the backseat and his paycheck was in the front. Authorities at the time assumed he'd left of his own accord, but as time passed and no one heard from him, they began to suspect foul play. It's unclear what, if any, investigation was done at the time, as Bacon's file has been purged from the state police archives.

In January 2009, Nelson E. Costello was arrested and charged with murder and two counts of witness tampering in Bacon's case. Costello was Bacon's age and worked as a constable in Waterford, New York in 1969. He carried a gun as part of his job. Costello later moved to Prescott, Arizona. A photograph of him is posted below this case summary. In October 2008, when he realized the police were investigating him for Bacon's possible homicide, Costello allegedly contacted a witness twice and tried to stop the person from giving information to investigators.

Authorities believe Costello killed Bacon in a rivalry over a woman whom Bacon was engaged to. They think Bacon was shot to death at Alcathy's Marina on Flight Lock Road in Waterford. They don't believe Costello was on duty at the time of the murder. Bacon's body may have been buried either along the Hudson River in Troy, New York, or out of state, possibly in Virginia or elsewhere in the southern United States. Costello allegedly had an accomplice who helped him dispose of Bacon's body, but the accomplice cannot be charged because the statute of limitations has run out.

Bacon lived in the 300 block of Hillcrest Street in North Troy, New York in 1969; the area is now part of Schaghticoke, New York. He dropped out of Lansingburgh High School and joined the Navy; he was a member of the Navy Reserves at the time of his disappearance. Foul play is suspected in his case due to the circumstances involved.

Above: Nelson Costello in 2009