This is one of the most searched questions about security work in Ontario, and it is also one of the most misunderstood. So let me make it as simple as I can.
As a security guard in Ontario, your legal authority comes from exactly two places. That is it. Just two.
One: anything that any regular citizen can do under the law. Two: whatever authority the property owner has delegated to you, usually through your site's standard operating procedures.
There is no third source. There is no special power that comes with the uniform. There is no extra authority that comes with the licence. If you understand these two things and what falls under each one, you understand the full scope of what you can and cannot do.
Every person in Canada, security guard or not, has the right to make a citizen's arrest under Section 494 of the Criminal Code. As a security guard, you are using this exact same authority. You do not get an upgraded version of it.
Under Section 494(1), any person can arrest someone they find committing an indictable offence. This means serious criminal offences like theft, assault, or break and enter. You must personally witness the offence. Suspicion is not enough.
Under Section 494(2), a property owner or someone authorized by the property owner, which includes you as a security guard, can arrest someone they find committing any criminal offence on or in relation to that property. This is slightly broader than 494(1) because it covers all criminal offences, not just indictable ones, but it is limited to the property you are authorized to protect.
Under Section 30, any person can intervene to prevent a breach of the peace. This is not an arrest power exactly, but it allows you to act to stop a situation from escalating into violence.
And one thing a lot of guards do not realize: if someone assaults you, you can arrest them for that assault. You personally witnessed the offence because it happened to you. A lot of guards take abuse and assume it is just part of the job. It is not. You have the same right as any citizen to respond to being assaulted, and if you want to press charges, you can make that arrest and hand the person over to police. Do not let anyone make you feel like being in uniform means you have to accept being hit.
The second source of your authority comes from the property owner. When you are working as a security guard, you are acting as the property owner's agent. Under the Trespass to Property Act, that gives you the authority to control access to the property on the owner's behalf.
This means you can ask someone to leave private property. If they refuse after being given notice, you can arrest them for trespassing. You can also bar someone from the property, meaning they are formally told they are not allowed to return. If a barred person comes back, they are trespassing from the moment they set foot on the property.
Your site's standard operating procedures will tell you specifically how the property owner wants you to handle these situations. Follow your SOPs. They are the practical expression of the authority the property owner has given you.
This is just as important as knowing what you can do.
You cannot detain someone for questioning. Unless you are making a lawful arrest, you have no authority to hold anyone. This is a major difference between security guards and police, and it is one of the most common mistakes new guards make.
You cannot arrest someone for a provincial offence or a bylaw violation. For example, if someone is smoking within nine metres of a building entrance, that is a violation of the Smoke-Free Ontario Act. You can ask them to move. But you cannot arrest them for it. That is enforced by bylaw officers and tobacco enforcement officers, not security guards.
You cannot use excessive force. You are allowed to use reasonable force to make and maintain a lawful arrest, to defend yourself or others from harm, and to enforce a trespass notice. But reasonable means the minimum necessary. If you use more force than the situation requires, you are the one who could be charged with assault.
You cannot search someone unless they are under lawful arrest, and even then, the search must be for safety reasons. You cannot search someone just because you are suspicious.
And you cannot force someone to show you their identification the way police can. However, if showing identification is part of the property's access rules, for example signing in at a front desk or presenting ID to enter a building, you can ask for it as part of enforcing those rules. If they refuse, you can deny them entry or ask them to leave the property. But outside of property rules or a lawful arrest, no one is required to give you their name or identification just because you are wearing a uniform.
This is something every guard needs to understand before they ever find themselves in a situation where an arrest might be necessary.
Once you tell someone they are under arrest, you cannot take it back. You cannot change your mind. You cannot decide it is not worth the hassle. You have made a legal declaration, and from that point forward, you are required to detain that person and hand them over to police as soon as possible.
This also means you have to stay. If your shift is ending and police have not arrived yet, you do not hand the arrested person over to the guard coming in to relieve you. You made the arrest. You stay until the police arrive. Sometimes that takes hours. That is the reality of it.
So before you say those words, be absolutely sure. Be sure that a criminal offence was committed. Be sure that you witnessed it. Be sure that you can articulate exactly what happened and why you made the decision to arrest. Because you will have to explain it, whether to your supervisor, to the police, or potentially in court.
This is a practical point that catches a lot of guards off guard, no pun intended.
You need to know exactly where your property ends and where public property begins. If you are covering a building in a busy area, the sidewalk and the street outside your building are almost certainly city property, not your client's property. You cannot enforce the Trespass to Property Act on property that does not belong to your client.
That said, there is a common situation that confuses people. If someone who is barred from your property was on the property and then steps onto city property, you can still inform them that they are barred. You are giving them notice, not enforcing a trespass at that moment. The bar applies to private property, and you are simply telling them it exists. What matters is what property the bar applies to, not where the person is standing when you tell them about it.
But when it comes to actually making an arrest for trespassing, it is always safer to do that while the person is on your property. Once they have left, your authority under the Trespass to Property Act becomes less clear, and anything you do off property is harder to justify if it is ever challenged.
The law tells you what you can do. Your experience and your judgment tell you what you should do. Those are not always the same thing.
If someone who was previously barred walks onto the property and sits on a bench without bothering anyone, you have the legal right to arrest them for trespassing. But should you? That depends on the situation, your site's procedures, and whether the arrest is actually solving a problem or creating one.
I have seen guards who wanted to arrest every trespasser every time they showed up. In reality, you will encounter the same people repeatedly, especially at busy or public-facing sites. You will get to know the regulars. Not every encounter needs to end in an arrest, and over time you develop a sense for when intervention is necessary and when it is not.
But if someone else, a tenant, a visitor, a member of the public, is asking you to act, or if the person is causing harm or disruption, that changes the calculation. Your job is to use good judgment, follow your SOPs, and always be able to explain why you did or did not act.
You are not police. You do not have police powers. Your authority comes from the same citizen's arrest laws that apply to everyone, plus whatever the property owner has authorized you to do on their behalf.
Follow your SOPs. Know your property lines. Never say "you are under arrest" unless you are certain. Use reasonable force and nothing more. And always be able to explain your reasoning.
If you keep those things in mind, you will stay on the right side of the law for your entire career.
Mary is the founder of Calrex Training Academy and has worked in the Ontario security industry for over 15 years, starting as a security guard and moving through roles in dispatching, supervision, and operations before specializing in emergency management and data analytics. She has hired and interviewed security guards and writes about security careers, licensing, and what it actually takes to succeed in this industry.