Driving around his adopted hometown of Miami on Wednesday night, 29-year-old Chicago native Phillip Agnew didn't feel safe. He never does. Not unless he's in his own neighborhood.

"If an officer pulled up right now I'd be afraid," he told MTV News. "Just like I have been ever since I first started driving."

Three years after unarmed 17-year-old high school student Trayvon Martin was fatally shot by neighborhood watchman George Zimmerman in a gated community in Sanford, Florida, Agnew still can't help looking over his shoulder.

Young black men -- including Mike Brown in Ferguson, Missouri and 12-year-old Tamir Rice in Cleveland -- have continued to meet violent deaths since the morning of February 26, 2012, when Zimmerman claimed he acted in self-defense after Martin attacked him.

Still, something has changed.

"Trayvon Martin was, I believe, the beginning of a heightened awareness of violence against youth," Daryl Parks, an attorney whose firm represents the Martin family, told MTV News in a phone call on Wednesday. "It brought to light the issue of gun violence, but also it began the whole awareness of all life matters. And that’s an issue that for so long as a country we have struggled with."

And if Agnew has his way, the generation of teen activists he's training will stop penning eulogies and start organizing for a better future.

A Death That Brought A Movement To Life

"The conversation now is, 'Do we have the right to live in this country?' " said Agnew, one of the co-founders of the Florida-based social justice group Dream Defenders, which organized after the Martin case. "It's a sad thing to be discussing in a land that is supposed to be one of democracy ... but people are in a place where they're saying, 'We're not going to take it anymore.' "

Agnew knows that he and his 100-plus team of young volunteers (some as young as 15 and 16) can't be on the street every minute to save every person who has a potentially deadly interaction with authorities. After the Martin case, though, he's seen a major shift. And the group is channeling that newfound hope into grassroots organizing, town halls and trainings from Orlando to Tampa and Tallahassee to Ft. Lauderdale.

'Trayvon is the most well-known martyr of our generation.'

On July 13, 2013, a jury acquitted Zimmerman of second-degree murder and manslaughter charge. This week, the Justice Department announced that there wasn't enough evidence for a federal hate crime prosecution. But on the third anniversary of Trayvon's killing, Parks and other activists on the ground in Florida believe that there's reason to have hope -- and to stay vigilant.

Parks said Martin's death sparked a movement that continues today in the "hands up" protest against the killing of 18-year-old Brown by a Ferguson police officer and the "I Can't Breathe" mantra spawned by the death of Eric Garner at the hands of a Staten Island, New York, police officer.

"I think the story is bigger than that community [in Sanford]," Parks told us. "It just happened to be where it happened."

"People are becoming more active and proactive so we can save lives instead of eulogizing people," Agnew agreed. "Trayvon is the most well-known martyr of our generation. ... He died because of the color of his skin, and the people that came out of that movement will never forget his name, his face ... Skittles and iced tea. It is imprinted in all our collective memories."

It Will Happen Again, But This Time The Streets Are Watching

Last summer, Parks joined Martin’s mother, Sybrina Fulton, and the parents of Mike Brown to the United Nations, where the families testified before panels on racial discrimination and torture.

He said the testimony on a world stage were major moments in the movement to end violence against young black men. Even so, he and Agnew aren't under the illusion that the struggle is over. Just this month, police in Miami Gardens killed 25-year-old Lavall Hall, who officers said attacked them with a broom stick.

"It might happen again, but if it happens again, and it will, at least there’s an awareness now that people are a bit more focused on the loss of life and what it means," Parks said. "People who commit these atrocities now know that there is someone who might do something about it.”

The Way Forward

At a time when hashtag activism is easy, Agnew is pushing for a change that he hopes will uplift a generation and get them to use their phones and their voices.

And that, for him, is the true legacy of Trayvon Martin, who would have turned 20 this month.

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