The 19:40 Detention in the Stockroom
You are the only SPP holder on the shop floor of a 1,200 sq ft electronics shop in Mong Kok on a Saturday night. At 19:40 you watch a 15-year-old put a HK$899 pair of earphones into his backpack, walk past the tills and leave without paying. You stop him on the pavement. He pulls away, so you and a stockroom colleague - who holds no SPP - hold his arms and take him into the 2 m × 2 m stockroom at the back. Your colleague handcuffs him to a chair. At 20:05, while waiting, you open the backpack and find the earphones and a foldable knife. Your manager is at a supplier dinner and will not be back before 22:00; he texts 'keep him there until I get back'. The boy says he feels faint, asks for water, and says his mother is waiting for him at the MTR exit. The police station is 600 m away.
1. Were you entitled to stop and hold the boy at all? Identify the lawful basis, its purpose and its limits.
Read the worked answer
Yes - but for one narrow purpose.
Lawful basis. Theft under the Theft Ordinance (Cap. 210) carries a maximum of 10 years' imprisonment. Because it is punishable by more than 12 months, it is an arrestable offence under the Interpretation and General Clauses Ordinance (Cap. 1). Section 101 of the Criminal Procedure Ordinance (Cap. 221) lets any person, not just a police officer, arrest without warrant someone he reasonably believes is committing or has committed an arrestable offence.
What that does not give you. The power exists so the person can be handed to the police. It is not a power to investigate, to interrogate, to recover property, to punish, or to hold someone until a manager is free. Every minute of restraint after the point where the arrest purpose is met needs its own justification, and force must be reasonable and no more than necessary at each stage - the pull-away justifies a firmer grip, not handcuffs.
Why the facts matter. You saw the concealment and the exit, so your belief was reasonable at 19:40. But the justification started weakening the moment he stopped resisting and you started waiting for a manager rather than calling the police 600 m away.
2. Assess three decisions taken by you and your colleague: the handcuffing, the search of the backpack, and waiting for the manager.
Read the worked answer
Handcuffing a compliant 15-year-old - not justified. Handcuffs are a significant use of force, not a routine restraint. They are defensible only where there is a real, present risk of escape or of harm to someone. Two adults, one teenager, a closed stockroom: the risk is low. Handcuffing him to a fixed chair also creates a serious injury risk if he faints or struggles. If cuffs are ever used they must be double-locked, checked regularly, removed as soon as the risk passes, and recorded with times.
Searching the backpack - no power. A security guard has no statutory power to search a person or their property on arrest. A search is lawful only with consent or under a specific power that police officers have and you do not. Opening the bag without consent is at best a trespass to goods and at worst an assault, and it contaminates the case: a court will ask why the goods were not simply left in place for police to recover.
Waiting until 22:00 - false imprisonment. Holding him for over two hours so the manager can 'see him' converts a lawful arrest into an unlawful detention. Delivery to police must be without unreasonable delay. This exposes you personally to a civil claim and to criminal liability, and it hands the defence its best argument.
3. Set out the correct sequence of actions from 19:40, dealing with the knife, the boy's condition and the record.
Read the worked answer
19:40–19:45 - stop with clear words. Identify yourself, say plainly what he is detained for, and use only the hold needed. Move him somewhere private but not locked, with a witness present.
Immediately - tell him why, and call 999. Explain in a language he understands that he is being arrested for suspected theft and that police are coming. The call takes seconds; do not wait for permission from a manager.
The knife - do not handle it. If you have already seen it, stop searching, do not move or open the bag further, and tell the police and the arriving officers. A 15-year-old with a knife is a risk factor that changes the restraint decision and must be passed on, not managed by you alone.
His condition. Faintness and a request for water are a medical issue, not a discipline issue. Sit him upright, give water, watch him, and call an ambulance if he deteriorates. Being unwell never justifies releasing him into the street - it justifies medical help and telling police.
Parent. Ask for a parent's contact and let the police notify them; do not interview him about the offence.
Record. Note the time of observation, the arrest, each use of force, the 999 call, the handover, and preserve the shop's own CCTV. Write your statement the same day, separately from your colleague's.