Section 11-2219. Notification to corporation counsel

The commissioner of
  motor vehicles shall promptly notify the corporation counsel of the city
  of any litigation instituted against him or  her  which  challenges  the
  constitutionality  or  validity  of any provision of this chapter, or of
  the enabling act pursuant to which it was adopted, or which attempts  to
  limit  or  question  the  applicability  of  either  such  law, and such
  notification shall include a copy of the papers served upon him.