The Washington Post reported on this case in December 2018:
A former Blackwater security guard was convicted of first-degree murder Wednesday for killing the first of 14 unarmed civilians in a barrage of gunfire in a crowded Baghdad traffic circle in 2007, an episode that drew international condemnation during the Iraq War.
It was the second time a federal jury in Washington convicted Nicholas A. Slatten, 35, of murder in the death of 19-year-old Ahmed Haithem Ahmed Al Rubia’y. His 2014 conviction was overturned on appeal, and a second trial last summer ended in a hung jury. Slatten now faces a mandatory life sentence without parole.
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Three other Blackwater guards who were part of Slatten’s convoy also were convicted in 2014, of manslaughter and other charges. The verdicts for Paul A. Slough, Evan S. Liberty and Dustin L. Heard were not reversed, but the 30-year sentences they received were vacated on appeal. No sentencing date has been set for any of the four defendants, all of whom are in custody.
As mentioned above, Slatten is a former security contractor with the Blackwater mercenary company who was found guilty of first-degree murder in December 2018 for his role in the September 2007 massacre of unarmed Iraqi civilians in Nisour Square, Baghdad, by several Blackwater employees. Fourteen Iraqis were killed and a further 18 were wounded in the unprovoked massacre, which prosecutors said Slatten initiated by being the first to fire. Slatten’s conviction was a long time in coming, with the first charges against him and other Blackwater members thrown out in 2009.
The case was later picked up with new evidence and Slatten was convicted of murder in 2014. An appeals court overturned this first conviction and ordered a new trial for Slatten, which initially ended in a mistrial. According to prosecutors, Slatten had told members of his team that Iraqi “people’s lives are not worth anything” and “they’re not even humans, they are animals.” He also expressed no remorse for the killings in a September 2017 interview with USA Today, saying that the only massacre was “a massacre of justice” against him and calling himself “a POW in my own country.”
The New York Times reported in May that Trump was considering issuing pardons for several American military members convicted or accused of war crimes, including Slatten. The Daily Beast subsequently reported that Hegseth was personally lobbying Trump for the pardons.