The city's Civilian Complaint Review Board is promising a thorough review of its police chokehold complaints following the death of a man during an arrest on Staten Island.
The new head of the board, Richard Emery, said it will carry out a study that will try to determine what leads officers to use the illegal maneuver.
It also hopes to provide information to the department to help it better train police in the future.
The review comes after the death of 43-year-old Eric Garner.
Garner died Thursday while police were trying to place him under arrest on Staten Island for allegedly selling illegal cigarettes.
Garner is seen in video published by the Daily News being taken down by four officers as he complains about not being able to breathe.
Emery said the CCRB will look into every chokehold complaint since 2009.
The board reports that of the more than 450 cases that were fully investigated during that time period, nine allegations were substantiated.
Meanwhile, Garner's family joined the Rev. Al Sharpton Saturday for a rally at the National Action Network.
Garner's wife, Esaw Garner, collapsed with grief during Sharpton's speech, and she and Garner's mother were in tears throughout the speech.
"The issue is how an unarmed man was subjected to a chokehold, and the result is, he is no longer with us," Sharpton said.
The family then came to a community center on Staten Island before marching to the exact spot that Eric Garner was killed.
They ended the march at the steps of the 120th Precinct.
Eric Garner's family is demanding an immediate, thorough and complete investigation into his death.
"My son is missing his dad," Esaw Garner said. "He's leaving for college on August 5, a full scholarship in basketball, and his father didn't get to see him step into that school."
His sister, Ellisha Flagg, praised the work of many police officers.
"There are good officers. There are officers who are good for us," Flagg said. "And it messes it up because once bad officers do something to somebody, everybody looks at all of them wrong. And that's sad. I feel bad for them."
Many people NY1 spoke with said in their eyes, the amount of force used by the officers was not proportionate to the offense of selling cigarettes illegally.
"He choked him," said one person at the march. "He wasn't being violent. He didn't hurt any other citizens. What's the reason to try and put him in a chokehold that you've explicitly been told not to use?"
"We are here today to stop the violence," said another person at the march. "This is for Eric, AKA Big E, AKA my big brother. We love you. We're going to miss you."
The internal affairs division of the New York City Police Department is investigating.
The two officers involved have been placed on desk duty.
The medical examiner has not yet determined a cause of death.
NY1 is told that there will be a funeral Wednesday at Bethel Baptist Church in Brooklyn.