Black Lives Matter Finds 'Renewed Focus' 5 Years After Trayvon Martin

It's been five years since the death of Trayvon Martin — and the outrage that sparked the Black Lives Matter movement. Martin — 17 years old, black and unarmed — was shot by George Zimmerman, a neighborhood watch volunteer in Sanford, Fla. Zimmerman was charged with second-degree murder and manslaughter. He claimed self-defense, and was later acquitted . After the verdict, there were demonstrations — and an emotional Facebook post by an activist named Alicia Garza. It read, in part: "Black people. I love you. I love us. Our lives matter." That phrase was streamlined by her friend, Patrisse Khan-Cullors, and with the help of a third friend, Opal Tometi, "black lives matter" became a hashtag, a rallying cry and eventually a protest movement that gained steam after police killed Michael Brown in Ferguson, Mo. Since then, much has changed, Khan-Cullors tells NPR's Audie Cornish. "In that moment, it wasn't popular to be in the streets. It wasn't a part of the mainstream dialogue," she says.