In many ways the discrepancy between Oscar Grant and Trayvon Martin reflects, at least in part, the immeasurable effort a group of family members and well-connected advocates exerted to wrench Martin’s story out of Florida and into national headlines. On February 28, two days after his death, his father placed a call to Benjamin Crump, a prominent civil-rights attorney in Florida, who had learned media-savvy trying the case of another black teen, beaten to death at a youth detention center in 2006. Crump lost that case, but he learned from his failure, and his strategy for Trayvon Martin involved making sure the case was tried in the press first.

The day after taking the case, Crump called Rev. Al Sharpton, who began a dogged campaign to mention the story on the airwaves. By March 5, Crump had found a publicist, Ryan Julison, to work the case pro bono. Julison began pitching the story to press using Martin’s family to elicit sympathy. “I got on the phone with Tracy Martin and I told him, ‘It’s not going to be any fun, but this is the only way to find justice,’” Julison explained to Reuters. “You are going to have to bare your soul and express your emotions and your inner grief.”

So Martin’s parents dedicated themselves to publicizing their plight, giving interviews, maintaining an active twitter account, and creating a foundation only a few weeks after their son’s death. “I think his parents were really courageous,” says Rashad Robinson, president of Color of Change.”Taking a moment that anyone would’ve totally understood if they went inward and decided to just mourn as a family, and realize that something was wrong, and instead reach out and push for the story to be told.” On March 7, Reuters ran a feature on Martin’s parents quest for justice; the next day CBS This Morning filmed a segment.

A few days later, a 31-year-old attorney living in Washington DC read the Reuters story and filled out a Change.org petition, calling for Zimmerman’s arrest; Jon Perri, a campaign director at Change.org, saw a chance to make the cause spread. “The petitions that are going to be the most successful are those that tell a personal story about whomever is going to be affected,” said Perri. He contacted Martin’s parents, rewrote the document to include family stories, and transferred the petition to their name. He sent the petition in an email to about a million Change.org users; 10 days later, the document had over a million signatures. (Researchers at the MIT media lab tracked Martin’s story through the press and found that it was his parents and advocates, not the Internet, that really got the word out.)

Back in Oakland in 2009, activists had to raise a similar stink to demand Mehserle’s arrest. (Like with Zimmerman, Mehserle’s arrest wasn’t immediate; it took two weeks for him to be charged after the shooting.) But Grant’s family played a less pivotal role in the coverage.

Alexis Sobel Fitts is an assistant editor at CJR. Follow her on Twitter at @fittsofalexis