Criminal Code of Canada
The Criminal Code is the source of the only powers a private investigator can exercise over other people - and they are the same powers any private citizen holds. Exam questions test arrest and use-of-force rules, the offences most often investigated, and the limits on search, detention and interception.
Citizen's arrest (s. 494)
Section 494(1) allows anyone to arrest without warrant a person found committing an indictable offence, or a person who on reasonable grounds is believed to have committed a criminal offence and is escaping from and freshly pursued by those with lawful authority. Section 494(2) gives owners and their agents, including loss-prevention staff, power to arrest a person found committing a criminal offence on or in relation to property they control, within a reasonable time. The arrested person must be delivered to a peace officer forthwith.
Force and defence
Section 25 permits only the force necessary and proportionate to the circumstances; s. 26 makes excessive force an offence. Sections 34 and 35 set out self-defence and defence of property; both require a reasonable response to an actual or perceived threat.
Investigative limits
A private investigator has no power to search a person or premises, detain for questioning, compel production of records, or intercept private communications. Section 184 makes interception of a private communication an offence unless a party consents or judicial authorisation exists. Charter ss. 8 and 9 constrain state actors; an investigator acting as an agent of police inherits those constraints.
Worked example
A loss-prevention officer sees a shopper conceal merchandise, pass the last point of sale and leave the store. At the door she identifies herself, tells the person they are under arrest for theft and asks them to return. The person complies, is walked to the office and handed to police eight minutes later. The arrest is lawful under s. 494(2): the offence was committed on the property, the person was found committing it, and delivery was forthwith. Restraining the same person on the street the next day, with no fresh pursuit, would not be.
Traps
Arresting someone who has already left and is not freshly pursued; holding a person while 'we sort it out' instead of calling police; assuming a citizen's arrest carries a power to search bags; and believing a store's private status exempts the investigator from the Code.