The Criminal Code permits private prosecutions. 

In the usual course, criminal proceedings are commenced or instituted by laying an information before a justice alleging the commission of an offence [FN].  

A private informant may lay an information provided he/she does so in conformity with section 504 of the Criminal Code.

As long as the information alleges an offence known to law and is facially compliant with the requirements of the Criminal Code, the justice must receive the information.  The justice takes the information under oath and affixes his or her signature to the jurat on the written Form 2.

R. v. McHale, 2010 ONCA 361, at para. 42; see section 504, Criminal Code.

But the laying of the information does not compel the person named as the accused to attend court to answer to the charge.

Where an information laid by a private informant has been received by a justice, the justice must refer it to a provincial court judge or a designated justice of the peace to consider whether to issue process (a summons or a warrant) to compel the appearance of the person charged. 

See section 507.1, Criminal Code.  

The hearing to determine the issue of whether to issue process to compel the appearance of the named accused to answer the charge is known as a pre­-enquette hearing.

In the context of private prosecutions, the pre-enquette hearing is governed by section 507.1, Criminal Code.

Notice to the Attorney-General

 In order for process to be issued, the Attorney General must receive a copy of the private information and reasonable notice of the pre-enquette hearing:

See ss. 507.1(3)(b) and (c).

The Criminal Code does not provide a specific form of notice.

The Hearing

The Attorney General must have an opportunity to attend the pre-enquette hearing and may cross-examine and call witnesses and present any relevant evidence.

See s. 507.1(3)(d).                   

However, the accused has no right to be present or to cross-examine the informant or any of the witnesses.  The purpose of the hearing is not to determine the guilt or innocence of the accused but simply to determine whether or not there are reasonable grounds to indicate that the accused should be required to answer to the charge of an offence.

R. v. Jean Talon Fashion Centre Inc. (1975),1975 CanLII 1184 (QC CS). 

In order for process to issue the evidence presented must discloses a prima facie case of the offences alleged, viz: there must be evidence of each essential element of the offence charged in the information.

McHale v. Ontario (Attorney General)2010 ONCA 361 (CanLII), at paragraph 74;

R. v. Grinshpun2004 BCCA 579 (CanLII), at paragraphs 32-33

The justice has a discretion not to issue process where he or she forms the opinion that the informant or his witnesses are not credible in the sense that they are mentally disordered or the charge is frivolous, vexatious or abusive.

R. v. Halik2010 ONSC 125 (CanLII), at paragraph 20.

A failure to consider all of the evidence would be an error going to jurisdiction, but the mere fact that a reviewing court might have come to a different conclusion with respect to the sufficiency of the evidence to establish a prima facie case would not entitle the reviewing court to intervene.

R. v. Deschamplain2004 SCC 76 (CanLII), at paragraph 37.

If, at the conclusion of the hearing, the judge or designated justice considers that a case for compelling the accused to attend court to answer to the charge has been made out, the judge or designated justice shall issue either a summons or a warrant for the arrest of the accused.

Section 507.1(2), Criminal Code.

Review of a Refusal to Issue Process

No appeal is available to review the refusal of a justice to issue process: 

Waskowec v. Ontario2014 ONSC 1646 (CanLII), at paragraph 10;  R. v. Grinshpunsupra, at paragraph 10.

The scope of review of a justice’s refusal to issue process is limited. It is open to an informant, however, to invoke the supervisory jurisdiction of the Superior Court of Justice by way of an application for mandamus with certiorari in aid. In order to succeed on such an application, the applicant must establish jurisdictional error. That, is, the applicant must show that the justice refused to exercise his or her statutory jurisdiction, acted in excess of it, lost it, or breached the principles of natural justice:

            R. v. Russell2001 SCC 53 (CanLII), at paragraph 19.

[FN]: An information is a sworn allegation of crime, and the person who lays an information is referred to as the informant. The term justice refers to a justice of the peace or a provincial court judge (see section 2, Criminal Code).