Section 137. Discipline

If  a charge may be made by any person against any
  officer or member of the police or fire departments  that  he  has  been
  negligent  or  derelict in the performance of his official duties, or is
  incompetent or without capacity to perform the same or is guilty of some
  delinquency seriously affecting his general character or fitness for the
  office, the charge must be in writing, in the  form  prescribed  by  the
  rules  and  regulations of the commissioner of public safety, and a copy
  thereof  must  be  served  upon  the  accused  officer  or  member.  The
  commissioner  shall  then proceed to hear, try and determine the charge.
  The accused shall have the right to be present at his trial  and  to  be
  heard  in  person and by counsel and to give and furnish evidence in his
  defense. All trials shall be open to the public.  The  commissioner  has
  power  to  issue  subpoenas,  in  his  name, to compel the attendance of
  witnesses, and shall upon the oral application of the  accused  issue  a
  subpoena  on  the behalf of the accused, leaving the space for the names
  of his witnesses blank that  he  may  fill  in  their  names,  upon  any
  proceeding  authorized  by  the rules and regulations of the department,
  and any person served with a subpoena is bound to attend in obedience to
  the command thereof; and the commissioner shall compel the attendance of
  witnesses and compel them to testify in the same manner as in  the  case
  of  any  officer  or board authorized by law to issue subpoenas and take
  testimony. If the accused shall be  found  guilty  of  the  charge  made
  against him, the commissioner may punish him by reprimand, by forfeiting
  and  withholding  pay  for  a  period  not  to  exceed  thirty  days, by
  suspension without pay during a period not to exceed thirty days, or  by
  dismissal  from  office.   At any time within one year after the date of
  dismissal, any officer or member dismissed may make application  to  the
  commissioner  for reinstatement. Such application must be in writing and
  contain a release of the city from all claims for back compensation. The
  commissioner may, in his discretion, rehear and redetermine the  charges
  and  reinstate  such  officer or member, with or without an allowance of
  the whole or a part of the time since such dismissal to  be  applied  on
  his  time of service in the department, or may affirm such dismissal. At
  any time within one year after this chapter takes effect or  within  one
  year  after  the  date  of  resignation,  an  officer  or member who has
  resigned may make application to the commissioner for reinstatement  and
  the  commissioner  may,  in  his discretion, reinstate him, but the time
  between the date of resignation and reinstatement shall not apply on his
  time of service in the department.