a judge has sentenced former blackwater guard nicholas slatten to life in prison for his role in a 2007 shooting that killed 14 and wounded 17 .
charges against paul slough , evan liberty and dustin heard included dozens of counts of manslaughter and attempted manslaughter .
the former blackwater guards were convicted in october on a combined 33 counts including manslaughter , attempted manslaughter and murder .
they left behind a hellish scene in a baghdad traffic circle where bombed out and bloodied cars littered a street strewn with bodies .