The grand jury had been considering the case since shortly after the March 29 incident, which has led to much discussion on Capitol Hill about race and the conduct of lawmakers and the officers who protect them.

"We respect the decision of the grand jury in this difficult matter," said U.S. Attorney Kenneth Wainstein.

McKinney did not immediately comment.

Wainstein's statement, released late Friday, also included support for the officer involved, Paul McKenna, and the Capitol Police. He said, "This is a tremendously difficult job, and it is one that Officer McKenna and his colleagues perform with the utmost professionalism and dignity."

With that, Wainstein closed a case that has simmered with racial and political tension.

The encounter began when McKinney tried to enter a House office building without walking through a metal detector or wearing the lapel pin that identifies members of Congress.

McKenna did not recognize her as a member of Congress and asked her three times to stop. When she ignored him, he tried to stop her. McKinney then hit him.

McKinney described the encounter as "racial profiling," insisting she had been assaulted and had done nothing wrong.

McKinney is black. McKenna is white.

She received little public support for that stance, even within the Congressional Black Caucus.

Wainstein, meanwhile, referred the matter to a federal grand jury, which then subpoenaed several House aides thought to have witnessed the encounter. McKenna, too, testified.

Members of the CBC privately urged McKinney to put the matter behind her. The next morning, she appeared on the House floor to apologize.

"I am sorry that this misunderstanding happened at all, and I regret its escalation, and I apologize," McKinney, D-Ga., said April 6. "There should not have been any physical contact in this incident."

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