5. Decision to Prosecute

5.1   Section 15(1) of the Criminal Procedure Ordinance, Cap. 221 states:

“The Secretary for Justice shall not be bound to prosecute an accused person in any case in which he may be of opinion that the interests of public justice do not require his interference.”

5.2   That provision applies such discretion equally to the Director of Public Prosecutions and to prosecutors acting on behalf of the Secretary for Justice pursuant to delegations.

5.3   The effect of that provision is to endorse generally accepted and longstanding international practice under the common law – that the decision to prosecute includes two required components. The first is that the admissible evidence available is sufficient to justify instituting or continuing proceedings. The second is that the general public interest must require that the prosecution be conducted.

Sufficiency of Evidence

5.4   There must be legally sufficient evidence to support a prosecution; that is, evidence that is admissible and reliable and, together with any reasonable inferences able to be drawn from it, likely to prove the offence.

5.5   The test is whether the evidence demonstrates a reasonable prospect of conviction. To satisfy that test, a prosecutor must make prospective judgements about matters such as:

1. the evidence available;
2. any challenge that may be made to the admissibility and/or reliability of the evidence;
3. the availability, competence and credibility of witnesses, and their likely assessment by the court;
4. any contrary evidence that may reasonably be anticipated;
5. likely defences to be raised;
6. the way in which a reasonable tribunal of fact, properly instructed as to the law, will be likely to act on all of the evidence and arguments in the case.

5.6   A prosecutor will need to consider in relation to witnesses: the reliability of memory; any suggestion of exaggeration; any association with the accused (favourable or unfavourable); any motive not to tell the whole truth; availability; psychological or other personal characteristics (including in the case of a child or incapacitated witness); vulnerability to attack by the defence.

5.7   The public interest is not served by proceeding with cases that do not satisfy this test. The resources required to prosecute must be responsibly applied only to proceedings that will be fair and that are likely to be effective.

Public Interest

5.8   Even where the first component of the prosecution test is satisfied, a prosecutor must consider the second component, the requirements of the public interest.

5.9   There can be no exhaustive list of the considerations to be addressed when making this assessment, but they include:

1. the nature and circumstances of the offence, including any aggravating or extenuating circumstances;
2. the seriousness of the offence: more serious offences, including those where a victim has suffered significant harm or loss, or where there have been multiple victims, are more likely to be prosecuted in the public interest;
3. the effect of a prosecution on Hong Kong law enforcement priorities;
4. any delay in proceeding with a prosecution and its causes;
5. whether or not the offence is trivial, technical in nature, obsolete or obscure;
6. the level of the suspect’s culpability;
7. the involvement of other suspects in the commission of the offence;
8. any cooperation from the suspect with law enforcement or demonstrated remorse: the public interest may be served by not prosecuting a suspect who has made admissions, demonstrated remorse, compensated a victim and/or cooperated with authorities in the prosecution of others;
9. any criminal history of the suspect;
10. the attitude, age, nature or physical or psychological condition of the suspect, a witness and/or a victim;
11. the likely final disposition of the case;
12. the prevalence of the offence and any deterrent effect of a prosecution;
13. special circumstances that would affect the fairness of any proceedings;
14. the availability and efficacy of alternatives to prosecution, such as a caution, warning or other acceptable form of diversion.

Mental Health Issues

5.10   The criminal justice system operates to protect both the community and individual members of it. From time to time the prosecution may consider it appropriate to charge mentally ill persons with applicable offences principally in order to invoke the court’s jurisdiction to make beneficial orders for the management of the mentally ill, their protection and the protection of the community.