McDowell was a Human male who served in Starfleet in the late 24th century. In the 2360s, McDowell served aboard the USS Enterprise-D as a tactical and security officer. In 2368, Ensign McDowell was on duty when the Enterprise came to the aid of a damaged Romulan science vessel. During the incident, McDowell was left in command of the bridge on several occasions, including the memorial service of Ro Laren and Geordi La Forge. (TNG episode: "The Next Phase") The following year, McDowell had earned a promotion to lieutenant and served on the gamma shift. (TNG episode: "Chain of Command, Part II")