Every person who, being subpoenaed to attend as a witness before the Mayor, Controller, Treasurer, City Council or any committee thereof, or any board provided for in the City Charter, refuses or neglects, without lawful excuse, to attend pursuant to such subpoena, and every person who, being present before the Mayor, Controller, Treasurer, City Council or any committee thereof, or any board provided for in the City Charter, willfully refuses to be sworn or to answer any material and proper question, or to produce upon reasonable notice, any material and proper books, papers, or documents in their possession or under their control, is guilty of a misdemeanor.