Weeks after being released from prison, Meek Mill is leveraging his high-profile case and his popularity.

The rapper, who is signed to music mogul Jay-Z's label Roc Nation, has taken to advocating for sweeping reform of America's justice system. In a statement to CNBC, Jay-Z said Mill was "caught in a probation trap for years by a broken system," echoing the remarks of other prominent figures who rallied to Meek Mill's defense.

After serving nearly five months in prison, Mill told CNBC's "Squawk Box" this week that his situation is part of a "systemic issue" — but not one that boils down to just racism, as some other activists contend.

"It's not really about color," MILL said in an interview. "It's about environment and circumstance."

He added: "Small mistakes put me back in prison without even committing crime again or being a threat to my community," said the 31-year-old Philadelphia-born rapper, whose real name is Robert Rihmeek Williams, told CNBC.

Mill's ordeal began in November when a Pennsylvania judge sentenced him to up to four years in prison for violating probation from a decade-old weapon and drug case.

The sentencing stemmed from two arrests last year: The first, for an altercation at a Philadelphia airport; and the second, for popping a wheelie on a dirt bike while he was shooting a music video in the streets of New York City. Both cases were later dismissed.

Other prominent artists and athletes, including former San Francisco 49er quarterback Colin Kaepernick and comedian Kevin Hart, as well as billionaire businessmen Robert Kraft, owner of the New England Patriots, and Philadelphia 76ers co-owner Michael Rubin, also believed Mill was incarcerated unjustly, and spoke out against his sentence.

The judge's decision, which went against the recommendations of no prison time from the assistant district attorney and Mill's probation officer, prompted outrage across the country, with many expressing support using the "#FreeMeek" hashtag on social media.