Nicholas Slatten was convicted of first-degree murder, while Paul Slough, Evan Liberty and Dustin Heard were convicted of voluntary and attempted manslaughter, over the incident in which US contractors opened fire in busy traffic in a Baghdad square and killed 14 unarmed Iraqi civilians.
The four contractors, who worked for the private security firm Blackwater owned by the brother of Trump’s education secretary, were included in a wave of pre-Christmas pardons announced by the White House.
“Pardoning the Blackwater contractors is an affront to justice and to the victims of the Nisour Square massacre and their families,” Jelena Aparac, chair of the UN working group on the use of mercenaries, said in a statement.