Hong Kong adopts a two-tier police complaints system.  All complaints against the Police, irrespective of their origin, are referred to CAPO for investigation.  After CAPO has conducted the investigation, it will submit the investigation report, together with relevant files, documents and materials, to IPCC for scrutiny.

Reportable Complaint
As provided for in the IPCC Ordinance, CAPO has to submit all investigation reports on reportable complaints to IPCC for scrutiny.  A 'reportable complaint' is a public complaint, made in good faith, that relates to the conduct of a police officer while on duty or who identifies himself as a police officer while off duty.  The complainant should be the person directly affected by the police misconduct. 

However, investigation reports or information on the following complaints will not be submitted to IPCC:

Complaints arisen from the issue of a summons or imposition of a fixed penalty which solely relates to the validity of the issue; or Complaints lodged by a person in his official capacity as a member of the police force; or Complaints that fall under the scope of investigation of other statutory bodies.

Notifiable Complaint
Other than reportable complaints and the cases mentioned above which will not be submitted to IPCC, all complaints are 'notifiable complaints'.  For instance, complaints made by an anonymous complainant or by a complainant who is not the aggrieved party are notifiable complaints.

Notifiable complaints are outside the purview of IPCC but CAPO is required to regularly submit the summaries of such complaints to IPCC for examination.  This is to ensure that all complaints which should properly be categorised as reportable complaints are so categorised and that the investigations will consequentially be subject to IPCC's monitoring and review.