FILE - This combination made from file photo shows Blackwater guards, from left, Dustin Heard, Evan Liberty, Nicholas Slatten and Paul Slough. Supporters of the former contractors at Blackwater Worldwide had lobbied for the pardons, arguing that the men had been excessively punished in an investigation and prosecution they said was tainted. Blackwater contractors were notorious in Baghdad at the time and frequently accused of firing shots at the slightest pretext, including to clear their way in traffic. The shooting in the traffic circle stood out for the number killed, but was far from an isolated event in Iraq at the time. The Blackwater firm was founded by Erik Prince, an ally of Trump and the brother of Education Secretary Betsy DeVos.

2007: Military contractors working for Blackwater Worldwide allegedly shoot and kill 17 Iraqis in Baghdad's Nisour Square while clearing the way for a convoy of U.S. State Department vehicles. The Blackwater guards claimed the convoy was ambushed and they fired in self defense, but Iraqi authorities said the killings were unprovoked. The killings outraged Iraqis and strained relations between Iraq and Washington. Another guard struck a deal with prosecutors and pleaded guilty to one count each of manslaughter, attempted manslaughter, and aiding and abetting. Pictured here is a sign marking the entrance of Blackwater's training facility in Mount Carroll, Illinois, on Oct. 2, 2007.