- September 8 – 26-year-old James E. Herbert is shot to death by Irving L. Scott in an apartment at 2239 Castle Rock Square in Reston to settle an argument over a gambling game.
- September 10 – The Fairfax County Board of Supervisors votes to withdraw Fairfax County Police Department and Fairfax County Sheriff's Office trainees from the regional Northern Virginia Criminal Justice Academy.
- "Herndon Man Killed, Suspect Held." The Washington Post (1974-Current file): B4. ProQuest Historical Newspapers: The Washington Post (1877-1995). Sep 09 1984. Web. 2 Mar. 2012.
- Moore, Molly. "Fairfax Pullout Threatens Area Police Academy." The Washington Post (1974-Current file): 2. Sep 12 1984. ProQuest. Web. 17 Jan. 2014.
|Fairfax County by Year: 1984|
|August 1984||·||September||·||October 1984|