"We are giving Ms. DiFiori's office the opportunity to do the right thing by this family, but I assure you if it is not done, if there's no indictment we will go to the U.S. Attorney's Office and demand a civil rights investigation of this city," said Randolph McLaughlin, attorney.
Three months ago, White Plains Police responded to a medical alert call that the 68-year-old had accidentally pressed while sleeping.
Upon arriving, police claim they heard an emotionally disturbed Chamberlain screaming inside the apartment and at one point, he pulled out a knife.
Here's how police, back then, described what happened next:
"Officers first used electronic taser, hit victim and had no effect, while officers were retreating, officers used a beanbag shotgun," said David Chong, Public Safety Commissioner.
Seconds later, police shot and killed Chamberlain in a warranted use of deadly force, police insist.
But, as we reported, audio and video is raising serious questions about the police version of events according to the family and their attorneys who recently were allowed to listen and view it.
"Did I see anything that would warrant their action, not at all. My father, when the door was busted down was eight to 10 feet away from them with hands down to his side, that's not an aggressive act," Kenneth Chamberlain, Jr. said.
"If you are in home and sleeping at 5 in the morning and law enforcement comes on a medical call, you should not have your door broken down and you should not end up dead," said Mayo Bartlett, attorney.
The District Attorney says, "In the coming weeks, the video and audio tapes, along with all other evidence will be presented to a Westchester County Grand Jury."
The son who has already seen some of that evidence swears it is proof police used excessive force.
"I am asking that these police officers be brought up on criminal charges," Chamberlain, Jr. said.
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