Grammy award-winning trumpeter Irvin Mayfield and his business partner Ronald Markham are expected to appear in federal court Thursday.

Thursday's appearance is the first since Mayfield was indicted in December for 19 federal counts including conspiracy, wire fraud, mail fraud, money laundering and obstruction of justice.

The criminal charges come more than two-and-a-half years after WWL-TV began a series of investigative reports exposing how Mayfield had used his position running the city's public library support charity to funnel money to a jazz orchestra he founded, to another nonprofit bank account he controlled and, in some cases, to directly feed his lavish lifestyle.

Irvin Mayfield, the Grammy-winning trumpeter who became a key cultural figure after Hurricane Katrina.

READ MORE: Jazz trumpeter Irvin Mayfield indicted by federal grand jury on 19 counts