A Queens grand jury failed to indict Detective Hassan Hamdy, the police officer who shot and killed Noel Polanco. The NYPD has now filed departmental charges against him. View Full Caption Victor Alcorn/Splash

NEW YORK CITY — The NYPD detective who shot and killed unarmed National Guardsman Noel Polanco during a car stop has been hit with a departmental charge in connection with the death, DNAinfo New York has learned.

Detective Hassan Hamdy, 40, was charged late Thursday with a single count: “failure to employ proper tactics that caused a civilian’s death,” according to sources.

There was no explanation what the proper tactics should have been, the sources said. If found guilty, the charge could lead to Hamdy's dismissal from the NYPD.

In addition to Hamdy, Sergeant Thomas Glaudino, a 20-year veteran, who was responsible for the Emergency Services Unit officers that morning, was charged with failing to supervise his team to prevent the alleged tactical mistakes, the sources said.

A Queens grand jury declined to indict Hamdy, a 15-year veteran and former U.S. Marine, of any criminal wrongdoing last year.

"This is a bureaucratic witch hunt," declared Robert Ganley, vice president of the sergeants' union.

Polanco, 22, had been driving his Honda Fit car on the Grand Central Parkway in Queens at 5 a.m. on Oct. 4, 2012, after drinking at a hookah bar in Astoria where he worked.

He was driving in and out of traffic when he passed two unmarked Emergency Service Unit vans filled with officers who were heading to Brooklyn to execute a warrant.

Glaudino, a sergeant for 12 years, gave the green light to stop Polanco because he feared Polanco might crash his car and injure his passengers — a cocktail waitress in the front seat and an off-duty female police officer who was sleeping in the back seat.

Despite seeing the lights and sirens, Polanco refused to stop, police said, forcing the officers to chase him and eventually box him in along the parkway divider.

Hamdy then approached Polanco's car from the passenger side. He fired once after he said Polanco failed to “show his hands” and made a sudden reach toward the floor of the car.

Hamdy told the grand jury he feared Polanco was reaching for a weapon. He said he fired in self defense and the grand jury declined to indict him.

Polanco’s family expressed disappointment at the grand jury’s decision and later settled a civil lawsuit with the city for $2.5 million.

The NYPD's decision to file charges stunned Hamdy's colleagues.

“The detective acted in good faith and was not indicted and I don’t know what he could have done differently once the car stop was made,” one official said.

Ganley said NYPD brass "are searching for scapegoats when the fact is, if they did not pull (Polanco) over that morning, and someone was killed by him, then they would have gone after the officers for not taking action to prevent it."

"These officers did not violate any department guidelines," the source insisted.

Attempts to reach Polanco's family Thursday night were unsuccessful.