By Jim Melwert

PHILADELPHIA (CBS) – The mother of Trayvon Martin will speak today at the National Urban League meeting in Philadelphia.

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Day three of the four-day conference got underway with a presentation from attorney Benjamin Crump, one of the lawyers representing the parents of Trayvon Martin.

“If Trayvon would have been of legal age, and Trayvon would have had a permit to carry a gun and he would have defended himself against this strange man who followed him, would the ‘Stand Your Ground’ laws have vindicated Trayvon Martin?”

He says nothing will bring Martin back. Now, the effort needs to be preventing this from happening again.

“I know I’m preaching to the choir this morning, but this conversation has to get to the George Zimmermans of the world: that our children are not criminals. Our children are not thugs. Our children have the right to walk from the 7-11.”

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Later today, Sybrina Fulton will speak at a luncheon at noon at the annual conference. Fulton supports an investigation into whether her son’s killer could be charged under federal civil rights laws. A jury acquitted George Zimmerman of all criminal counts in Trayvon Martin’s death.

The conference at the Pennsylvania Convention Center is focusing, organizers say, on job creation, voting rights, and civil rights.

Yesterday, US Attorney General Eric Holder focused on voter registration, and access to the polls.

This morning, Congressman John Lewis, Reverend Al Sharpton and Jesse Jackson attended a panel discussion on the 50th anniversary of the March on Washington.

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