A federal judge says a New Jersey school is within its rights to fire a security guard who posted on Facebook describing two men accused of killing a police officer as "black thugs" and suggesting "all white people should start riots and scare the hell out of them."

U.S. District Judge Joseph Irenas ruled Thursday that Mary Czaplinski is not likely to win a lawsuit against the Vineland Public Schools asserting that the district violated her freedom of speech.

The guard was fired earlier this month after a post about the shooting in Philadelphia. She also wrote that she was "praying hard"for the slain police officer, who was black.

The district noted the student population in Vineland is diverse and questioned the guard's ability to be an "unbiased arbiter."