Section 389. Internal controls, rule-making, contracting

a. In accordance
  with the policies and procedures  established  by  the  mayor  for  this
  purpose,  heads  of  mayoral agencies shall maintain an internal control
  environment and system which is intended to maximize  the  effectiveness
  and  integrity  of  agency operations and to reduce the vulnerability of
  the agency to fraud, waste, abuse,  error,  conflict  of  interest,  and
  corruption.
    b.  Except  as  otherwise  provided  by law and in accordance with the
  provisions of the charter and other law, heads of mayoral agencies shall
  have the power to adopt  rules  to  carry  out  the  powers  and  duties
  delegated  to  the  agency head or the agency by or pursuant to federal,
  state or local law.
    c. Heads of mayoral agencies may, subject to the requirements  of  the
  charter,  other  law, and rules promulgated pursuant to them, and within
  appropriations therefor, enter into  contracts  and  make  purchases  to
  fulfill the duties assigned to them.