By Jim Williams

CHICAGO (CBS) — There was a volatile protest at City Hall Thursday morning over alleged police brutality.

Demonstrators stood outside the mayor’s office to protest police brutality, though most of the alleged cases they cited happened in the suburbs, CBS 2’s Jim Williams reports.

“What do we have to do for justice? Why do we have to march for justice? Why do we have to get angry for justice? Do we have to riot? Do we have to tear things down?” Aaron Watts said.

They charged that cops killed or injured innocent family members.

“These people should not have been executed by police,” said Mark Clemons, of the Campaign to End the Death Penalty.

The black community, they said, is under siege by violent officers.

But every weekend in Chicago, there are multiple shootings in African American neighborhoods, and most of the gunmen are not the police. So, Williams asked this question: “What is a greater threat to the black community, criminals and gang members on the street or Chicago police officers?”

That sparked an angry and emotional response from one of the news conference participants, who called it a “stupid” question.

David Lowery of the NAACP tried to answer it and said, “It’s not a stupid question.”

“The greater damage to the community is black officers and white officers who continue to kill our children because they have the position of power,” he said.

One of the protest organizers later said it was understandable that the woman had an emotional reaction to Jim’s question.

Her sister was killed last month when off-duty Chicago detective fired at a suspect. Police admit she was an innocent bystander.

Police said early March 21 the detective was pulling out of an alley in his car off the 3100 block of West 15th Place in the North Lawndale neighborhood, when he came across four people who were being loud and rowdy on the street.

Police say the detective rolled down the window of his vehicle to investigate, and saw a man approach him with a handgun, then allegedly point it at him. The off-duty detective shot in fear for his own life, the police union has said.

The man who allegedly had the gun – Antonio Cross, 39 – survived a gunshot wound to the hand and now stands charged with misdemeanor assault. Rekia Boyd, 22, was shot in the head and was later pronounced dead.

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