A federal grand jury is said to have begun hearing evidence in the case of Eric Garner, an unarmed black man who died after he was placed in a chokehold by a white police officer, NPR's Joel Rose reports, citing two sources familiar with the investigation.

The grand jury is determining whether Officer Daniel Pantaleo violated Garner's civil rights as he moved to arrest him for allegedly selling loose cigarettes.

If you remember, a New York grand jury declined to bring charges against Pantaleo back in December. Protestors took to the streets and in Washington, the Justice Department announced that it would launch a civil rights investigation into the case.

The Garner case first gained national attention in part because because of video captured by a bystander. It showed Garner in headlock repeatedly telling Pantaleo that he could not breathe.

The New York Daily News, which first reported the federal grand jury story, says that the Justice Department brought in Forrest Christian, a veteran civil rights division prosecutor, to handle the case.

The newspaper adds:

"The convening of the grand jury is a monumental step in the federal investigation that was launched in December 2014 immediately after a state grand jury declined to prosecute Pantaleo. It is unclear whether Pantaleo will testify before the federal grand jury, but federal prosecutors can use his testimony before the state grand jury."Christian is considered a rock star in the Justice Department. He received the Attorney General's Award for Exceptional Service for the successful prosecution of 10 New Orleans police officers convicted of fatally shooting innocent citizens on the Danziger Bridge after Hurricane Katrina."

Last summer, New York City reached a $5.9 million settlement with Garner's family. During a press conference, the family said they wanted Pantaleo to face federal charges.

"They deserve to be prosecuted. They treated my husband like an animal," said Garner's widow, Esaw Garner.

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