Crown Counsel has a different duty than other lawyers. Most lawyers have a duty to a client. But a Crown has a duty to see justice is done.
This means that a Crown is not there to "win" a case but rather is there to see cases with merit are fairly and properly tried. If the Crown concludes a case has no real merit or should not go ahead as contrary to the public interest the Crown should stop the prosecution.
In 1981 a Royal Commission in the United Kingdom wrote:
"The proper objective of a fair prosecution system is not therefore simply to prosecute the guilty and avoid prosecuting the innocent. It is rather to ensure that prosecutions are initiated only in those cases in which there is adequate evidence and where prosecution is justified in the public interest."
The role of a Crown is different from a defence lawyer's role. If an accused says to a defence lawyer "I am not pleading guilty and want a trial" the defence lawyer is to do a trial even if the case is pretty well hopeless and not a good idea for the community. Now the defence lawyer must give the best legal opinion to the accused but the accused decides what to do.
The Crown, by contrast, has discretion. The Crown decides whether to go ahead or not - and this happens all the time.
But the Crown's decision is not based on a whim. The Crown considers two factors in deciding whether to proceed: an evidentiary consideration, which requires there be a substantial likelihood of conviction, and a public interest test.
The evidentiary test is met when Crown counsel is satisfied there is a strong, solid case of substance to present to the court. If there is not the Crown will discontinue the prosecution.
If the Crown is satisfied that the evidentiary test is met, the Crown considers whether the public interest requires a prosecution. This is a complex question and very fact driven. The Alberta Department of Justice suggests the factors to consider include:
It is generally in the public interest to proceed with a prosecution where the following factors exist or are alleged.
the conduct was serious, because, for example:
weapons were used
violence was used or threatened
the conduct was planned, premeditated and/or motivated
there was significant harm, loss or injury caused to the complainant and/or the community
the victim was vulnerable (e.g., a child, a senior, a spouse, a person who was dependent upon the accused, a person who serves the public)
the offence involved an abuse of a position of authority or trust
the offence was directed at the administration of justice;
the accused's degree of culpability and responsibility was significant (especially if in relation to any other parties who were involved in the conduct);
the offence was motivated by discrimination against the complainant's ethnic or national origin, sex, religious beliefs, political views or sexual orientation;
owing to a previous related record or other antecedents, it is likely that, absent a prosecution, the accused will continue or repeat the conduct (i.e., there is a need for individual deterrence); and/or
there exists a need to denounce the conduct and deter others.
The following are some of the public interest factors that may militate against commencing or continuing a prosecution.
the offence is of a trivial or technical nature;
a conviction is likely to result in a very small or insignificant penalty;
the consequences of a prosecution or conviction would be unduly harsh or oppressive for the accused;
the accused has remedied the loss or harm (although accused persons must not avoid prosecution solely because they make restitution);
the accused has demonstrated genuine remorse and has steps taken towards rehabilitation (the significance of which must be assessed in the context of the seriousness of the offence);
the desired result could be achieved through an alternative to prosecution (e.g., the matter could be effectively addressed through the Alberta Adult Alternative Measures Program (see the guideline Adult Alternative Measures Program) when dealing with adult offenders, or the Youth Criminal Justice Act Extra-judicial Sanctions Program (see the guideline Youth Extrajudicial Sanctions Program) when in dealing with young persons);
the law that is alleged to have been breached is obsolete or obscure; and/or
a prosecution could publicize information that that could harm confidential informants, ongoing investigation, international relations or national security, or other important local and national interests.
The following are additional factors that may be considered in respect of the public interest criterion.
the circumstances of the accused, including his or her age, maturity, mental health, criminal antecedents (including other outstanding charges or extant court orders) and background;
the likely effect of a prosecution on public morale and the public's confidence in the justice system;
the length and expense of the trial when considered in relation to the seriousness or triviality of the offence, the likely sentence that would result from a conviction, and the attendant public benefit(s);
the degree of past or anticipated cooperation of the accused in the investigation, apprehension or prosecution of others (see also, the guidelines and practice memoranda pertaining to Informants);
the willingness and ability of witnesses, including – where necessary – the complainant, to testify in the proceedings;
the time which has elapsed since the offence was committed;
the availability of compensation, restitution, or reparation to any person or body upon a successful prosecution, including any entitlement criminal compensation, reparation or forfeiture if a prosecution action is taken; and/or
whether, due to the passage of time, the alleged offence is triable only on indictment.