Organizers of Common's #ImagineJustice concert estimate more than 30,000 people showed up for the free event. RSVPs were required online.

Common was joined by other artists like J.Cole, Goapele as as speakers like Von Jones. The purpose of the concert was to raise awareness for reforming the criminal justice system and kick off a 3-day campaign in the state Capitol.

"This is one of the greatest moments for me ever in my career, for me to be in Sacramento, performing at the Capitol, in support of changing our prison system. That's why I'm here," said Common.

The rapper and actor has long been known for his social activism, but only recently did he get involved with fighting for criminal justice.

"I didn't know much about the prison system or mass incarceration. I just connected with the issue after working on songs," said Common. "I'm for the youth. I want our youth to have opportunity but of course, people who are black and brown don't get a chance to get equal opportunities."

Common's social impact advisor Michael Latt said some of the topics that will be discussed with state legislators include gun enhancements, excessive sentencing, mass incarceration, and the bail system.

"Juveniles sentenced to life without parole is unjust," added Latt. "Reforming the bail system so we don't incriminate people for being poor.

"What I realized was that the criminal justice system had treated so many people unjustly and inhumanely," said Common. "Lives were being thrown away."

Common and Latt are also making sure they're actually spending time with the very people they're trying to help feel hope and redemption, themes their tour earlier this year was named after.

"I went to four California state prisons [earlier this year], went, listened and talked to [inmates]," said Common. "We can't come into places and say we know what they need. It's about interaction and listening. It's that process, so I went in and really digested what was going on."

Ladd adds that music is a tool they want to inspire hope.

"One guy told us, if you give us a little hope, we could move mountains," said Latt. "We felt these concerts were a great way to instill in these guys to want change and make a difference in their lives.

"I've had individuals come up and say 'I forgot we were in prison!' Some had never attended a concert, including 50-year-old men," said Common. "I have to say [the inmates] brought a lot to me too, just that experience. I met some of the most humane, most intelligent...some of the most significant people I've ever met in my life."

While bringing out over 30,000 people to the show already feels like a success for Common, that's just the beginning.

"Success will be when incarceration goes down in the state of California and across America, when education is teaching young people new things, how to be successful in life now .That's long term goals, but we are starting now."

For his fans who aren't politically aware, Common hopes the concert might motivate them to learn.

"It doesn't take much to start," said Common. "What I'm saying to the fans is you don't have to be Martin Luther King or Obama or Michelle Obama or Mother Teresa, but it starts with a simple cat of love and kindness to other people."