Here is a piece from DVIDS about the 2011 US Japan SOFA clarification. The article has this to say about the new rules regarding civilians:
Under the Military Extraterritorial Jurisdiction Act, SOFA civilians who commit certain crimes overseas can be extradited to the states to be tried in their local U.S. district court.
“The problem with that is it is hard to work,” said [Capt. Jonathan P. Stevens,trial counsel with Combat Logistics Regiment 37, 3d Marine Logistics Group,III MEF]. “All the witnesses and evidence are here, and you have to try to move it all to the states. Sometimes we’re unable to do that.” Additionally, a MEJA prosecution is reserved for serious felonies, said Stevens.
Serious felonies? Really, one year or more in prison is just about every non-traffic offense in Title 18, no?
Update: Here is a link to the original article on a .mil website.