 In July 2008 , United States District Judge Karl Forester ruled Delta will not be held liable for the crash , because while Comair is a wholly owned subsidiary of the Atlanta @-@ based airline , Comair maintains its own management and policies , and employs its own pilots . In December of the following year , Forester granted a passenger family 's motion for " partial summary judgment " determining , as a matter of law , that Comair 's flight crew was <unk> , and that this negligence was a substantial factor causing the crash of Flight 5191 . 
