Heavy D, whose real name is David Sparks, is in jail because he was found in contempt of court for repeatedly and willfully violating court orders related to a 2017 environmental lawsuit under the Clean Air Act. He owed approximately $844,000 in fines and attorney fees stemming from a case where he and his company were accused of selling diesel trucks that emitted illegal levels of pollution. Despite multiple court orders to pay these fees and provide financial disclosures, he did not comply, leading a federal judge to order his arrest and incarceration until he settles the owed amount or completes certain filings to address the court's requirements. This legal battle has been ongoing for years, and his arrest was a result of the court exhausting all other options to enforce compliance.