From Canadian Legal FAQs
After catching my daughter shoplifting, the store owner detained her in a back room of the store and told her he was going to call the police. Did he have the right to do that?
Yes. You may have heard the term "citizen's arrest". This means that any citizen has a limited right to arrest another person if they are seen committing an indictable offence or if they believe on reasonable and probable grounds that someone is committing a crime. The most common form of citizen's arrest involves shoplifting. These are usually made by store detectives or personnel. Having detained your daughter, the store owner must call the police immediately and let them take over as soon as they arrive.
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