As music's reigning power couple, Jay Z and Beyoncé are using their influence to spread the word about a cause they feel strongly about—achieving justice for Trayvon Martin.

Jay and Bey were spotted Saturday at a demonstration in lower Manhattan fighting against Florida's Stand Your Ground Law, the legislation that allowed George Zimmerman to avoid jail time in the February 2012 shooting death of 17-year-old Martin.

Al Sharpton, who organized the rally, spoke about the stars' support, referring to them as "two of the baddest artists of all time."

"Jay Z and Beyoncé said they didn't want to speak and they didn't come for a photo op," Sharpton said in an address to the crowd. "Jay Z told me, 'I'm a father, Beyoncé is a mother.' We all feel the pain and apprehension. The laws must protect everybody, or it doesn't protect anybody."

In addition to attending the rally, Jay Z and Beyoncé have also performed separate tributes to Martin.

Beyoncé dedicated a performance of Whitney Houston's "I Will Always Love You," to the fallen teen at a Nashville tour date immediately following the verdict in the case.

One week later, Jay Z took the stage with Justin Timberlake during their "Legends of Summer" show at Yankee Stadium and dedicated the closing number to Martin. As Timberlake sang the opening of "Forever Young," Jay Z told the crowd, "Get out your cell phone. Let's light the sky for Trayvon Martin tonight."

And Jay Z and Beyoncé are not the only celebs speaking out about the Martin case.

Stevie Wonder recently announced he would not play any more concerts in Florida until the Stand Your Ground Law is changed.

Click here to see rally photos of Jay Z and Beyoncé and check out Jay's concert tribute below.