ABC News takes a look back at the Black Lives Matter movement. The phrase "Black Lives Matter" was born in a Facebook post by Alicia Garza in response to the July 2013 acquittal of George Zimmerman, who fatally shot Martin. The movement emerged as a reaction to the perceived violence and systemic racism by police toward African-American communities.

People celebrate at George Floyd Square after the guilty verdict in the Derek Chauvin trial, April 20, 2021, in Minneapolis.
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