Beyonce and Jay Z joined the Florida teenager's mother as she spoke to crowds in Manhattan alongside the Reverend Al Sharpton.
The case has become a flashpoint in separate but converging national debates over self-defense laws, guns, and race relations.
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High profile: Trayvon's mother Sybrina Fulton, third from left, was joined by Beyonce, Jay Z and the Rev Al Sharpton
Star support: Beyonce and Jay Z join a Justice for Trayvon rally in New York