The Starfleet Intelligence officer who runs Miles O'Brien's undercover operation inside the Orion Syndicate.
Chadwick is Miles O'Brien's contact in Starfleet Intelligence during his undercover mission on Farius Prime in Honor Among Thieves. Once O'Brien uncovers a Starfleet officer secretly working for the Syndicate, Chadwick asks him to stay in place to learn more about the Dominion's involvement.
When O'Brien reports the plot to kill the Klingon ambassador, Chadwick chooses to tip off the Klingons and let them deal with Bilby and his men rather than arrest them, leaving O'Brien to wrestle with betraying a man who trusted him.