Investigations can also be initiated on The Ombudsman's own volition, without any complaint received, and he can publish anonymised investigation reports of public interest at any time.

The Ombudsman has the power to investigate complaints of non-compliance with the Code on Access to Information by the Hong Kong Police Force, the Independent Commission Against Corruption, the Hong Kong Auxiliary Police Force and the Secretariat of the Public Service Commission, in addition to Government departments and organisations under his jurisdiction.

However, there are some restrictions to The Ombudsman's powers under the Ordinance. For instance, he will not normally investigate complaints which have a statutory channel for appeal or objection, or where a similar complaint has been investigated and no maladministration has been found, or complaints which are trivial, frivolous, vexatious or made in bad faith.
 

In general, the Office will handle complaints by the following four methods:
 a. Internal Complaint Handling Programme ("INCH") - for less complex cases, the Office will undergo inquiry under INCH with the consent of the complainant. The Ombudsman will transfer the complaint to the complainee organisation(s), which will be responsible for replying directly to the complainant. The Ombudsman will monitor the reply made by the organisation(s) concerned and will intervene if the complaint is not handled properly or completely.

b. Rendering Assistance/Clarification ("RAC") - for dispute ongoing for some time or complainants do not consent to referral to complainee organisation(s) for replies, The Ombudsman will request the complainee organisation(s) to provide information and comments, The Ombudsman will then write to the complainant to explain or clarify the case. If serious maladministration is discovered in the process of investigation, a full investigation can be developed.

c. Mediation - with the voluntary consent of both the complainant and the organisation concerned, mediation may be adopted to settle a dispute. The two parties meet to resolve the dispute directly. The Ombudsman will act as a neutral mediator, and will not make any judgment or comment on the dispute.

d. Full Investigation - for complex cases involving issues of principle or serious maladministration, The Ombudsman will conduct a full investigation, with prior notice to the Head of the organisation under complaint. Full investigation involves examining documents, conducting site inspections and summoning witnesses, etc. If a complaint is substantiated, the Office will make recommendations to the organisation concerned and issue draft Investigation Report to the Head of the organisation for their comments. Subsequently the Office will monitor the implementation of recommendations by the organisation(s).

The number of complaints handled and concluded during the reporting year of 2009/10 are  5 869 and 4 775 respectively. On completion of full investigation of 126 cases and seven direct investigations, 141 and 62 recommendations respectively were made, that is a total of 203. As of March 31, 2010, 195 (96.1%) of them have been accepted by the organisations for implementation and six (3.0%) are still under consideration. Two have been dropped subsequently: one for practical reasons accepted by us and the other overtaken by events.