DENVER -- LeBron James spoke publicly Tuesday for the first time since a grand jury declined Monday to press charges against the police officers responsible for the November 2014 shooting death of Tamir Rice, a 12-year-old Cleveland native.

James said he was slow to react to the news because he was not informed on all the details pertaining to the case, but activists have started a social media campaign calling for James to sit out games in protest of the grand jury decision.

"For me, I've always been a guy who's took pride in knowledge of every situation that I've ever spoke on," James said following the Cavs' win over the Denver Nuggets. "And to be honest, I haven't really been on top of this issue. So it's hard for me to comment. I understand that any lives that [are] lost, what we want more than anything is prayer and the best for the family, for anyone. But for me to comment on the situation, I don't have enough knowledge about it."

James has become more and more outspoken regarding social issues facing the United States in recent years. His willingness to comment on issues, coupled with his immense fame and influence, caused activist and writer Tariq Touré to create the Twitter hashtag #NoJusticeNoLeBron, calling for James to sit in protest of the outcome of the Rice case. The hashtag was embraced by Black Lives Matter activists and gained moderate traction online.

"Gun violence and tragedies and kids losing lives at a young age, some way, somehow we need to understand that that matters more than just an individual," LeBron James said. Bart Young/NBAE via Getty Images

James said that, just like the particulars of the investigation into the police officers' actions against Rice, he was not fully informed about the calls for him to personally protest the lack of an indictment.

"I caught a little bit of it from my folks on the side saying that you guys might ask me about it, but I have no knowledge," James said. "I'm not much of a social media guy. I'm on it, for sure, but I'm not always looking at what's going on in it."

A reporter later asked what James could do, as someone in his position, to help enact the social change he wants to see in this country.

"First of all, I think I've been very outspoken about what I believe in," James said. "What hits home for me, what I am [knowledgeable] about. There's been so many more issues that's gone on that I haven't spoken about.

"There's been the San Bernardino massacre, there's been guys going in movie theaters, shooting up movie theaters, there's been other issues. Those are not something that ... I don't have much knowledge of so I don't speak about it. So for me ... if I feel like it's something that I have a lot of knowledge about [I'll add my voice to the issue], because I don't like to speak when I don't know about it.

"But I think the most important thing that we all need to understand, the most important thing, this issue is bigger than LeBron. This issue is bigger than me; it's about everyone. And gun violence and tragedies and kids losing lives at a young age, some way, somehow we need to understand that that matters more than just an individual."

James has lent his support to social issues in the past, starting in March 2012, when he and then-teammate Dwyane Wade organized a photo of the entire Miami Heat team wearing hooded sweatshirts, the same style of hoodie Trayvon Martin was wearing when he was shot by George Zimmerman. James posted the photo to social media along with the hashtag #wearetrayvonmartin.

Last season, James displayed a similar social consciousness, commenting on the death of Mike Brown in Ferguson, Missouri, and joining dozens of other NBA players in wearing an "I can't breathe" T-shirt during pregame warm-ups to identify with supporters of Eric Garner, another black man killed during a confrontation with police.

In October, he took to Twitter to offer his condolences on the death of a 5-month-old girl, Aavielle Wakefield, who was killed in a drive-by shooting in Cleveland. He later elaborated on his stance, saying, "There's no room for" gun violence.