CHAPTER II
FUNDAMENTAL RIGHTS AND FREEDOMS
46. Power of arrest and detention
No person shall be arrested or detained for an offence unless the arresting officer observes the offence being committed, or has reasonable and probable grounds or evidence to believe the person has committed an offence or is about to commit an offence, or under the authority of an arrest warrant issued by the court.
Fair trial standards
Rights during investigation - arbitrary arrest or detention and deprivation of liberty
EDIT.