The anguished mom whose unarmed National Guardsman son was shot dead by an NYPD cop last year demanded a federal probe of the killing yesterday, two days after a Queens grand jury declined to bring criminal charges against the detective.

“He is still a murderer no matter what, in my eyes,” Cecelia Reyes said of Detective Hassan Hamdy who fired a single fatal shot at driver Noel Polanco, 22, early on Oct. 4 near La Guardia Airport, following a high-speed chase on the Grand Central Parkway.

“You need to use your mind before you do something like this,” she said at the National Action Network in Harlem. “Someone in a position like this should think before they use their gun. It’s still murder to me. It’s still murder.”