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The Milwaukee police officer who shot and killed a black man in April won't be charged, a district attorney announced Monday. Milwaukee County District Attorney John T. Chisholm said that former Milwaukee police officer Christopher Manney "was justified in firing at Dontre Hamilton" because Hamilton had taken Manney's baton while the officer was responding to a complaint about a man sleeping in a public park, and the Manney was attempting to "stop the threat."

In a statement, Chisholm said "the more difficult issue" is determining whether Manney — who shot Hamilton at least 13 times — fired more shots than he needed to in order to subdue Hamilton. But many witnesses testified that Manney stopped firing when Hamilton fell to the ground, prompting Chisholm to rule that the numerous shots were a "defensive action forced upon him by Dontre Hamilton’s deadly attack with a police baton.”

In addition to an autopsy, a state investigation and an independent expert's investigation were conducted. The investigations were then reviewed by a prosecutor. "I am satisfied that we have done a very thorough, very independent investigation," Chisholm said. He added that he is "deeply aware" that his decision might cause protests, but "I can’t control outside events and I can’t allow outside events to control me."

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Milwaukee County Sheriff David A. Clarke requested National Guard support in anticipation of protests following the announcement. The request comes after protesters blocked traffic on Interstate 43 on Friday, leading to the arrest of 74 people.

Manney was fired by Milwaukee police Chief Edward Flynn in October, not because of his actions in the shooting but rather for failing to follow department rules in the moments leading up to the altercation, resulting in a struggle that left deadly force as the officer's only option.

The Hamilton family's attorney, Jonathan Safran, requested Monday that a federal investigation be conducted, "with the belief that federal law criminal civil rights charges are warranted in this case."

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Hamilton family seeks federal investigation into Red Arrow Park Shooting. http://t.co/ElzQblrnOQ pic.twitter.com/iM6SrG7ZAd — 620wtmj (@620wtmj) December 22, 2014

— Elisha Fieldstadt