The prosecution of civilians at court-martial has been an interesting development since the Article 2(a)(10), UCMJ, changes. For a little background see the earlier musings on this topic.
There has been only one private contractor ever indicted by the Department under MEJA for any sort of physically abusive or violent crime – Aaron Langston of Snowflake, Arizona, charged with assaulting a fellow contractor in Iraq with a knife. See United States v. Aaron Bridges Langston, CR-07-210-PHX (U.S. Dist. Ct., Dist. of Ariz., Indictment, Feb. 27, 2007).
Reported in, US military court-martialing civilian contractor Ali while DOJ slumbers, 19 May 2008.