Scene and Evidence Preservation: Lessons 2026

Lesson 1: Your role at a scene

A scene is any place where an incident happened and where there may be evidence: a break-in, an assault, a theft, a fire or a serious injury. As a security guard you are often the first person there. What you do in the first few minutes can decide whether evidence survives.

Your job is not to investigate. Police investigate crimes. Your job is to keep people safe, call the right help, protect the scene and the evidence, and write good notes. When police arrive, they take control and you follow their directions.

Priorities in order

1. Life safety. Check for danger, give first aid within your training and make sure 911 is called.
2. Call for help. Tell police, your supervisor or your dispatch what happened and where.
3. Protect the scene. Keep people out and stop evidence from being moved, damaged or lost.
4. Record. Write down times, what you saw, who was there and what you did.
5. Hand over. Brief police when they arrive and give them your notes and any items you protected.

If you arrest someone, remember that section 494(3) of the Criminal Code says anyone who is not a peace officer must deliver the arrested person to a peace officer forthwith, which means right away. Call police as soon as it is safe.

Lesson 2: Securing the scene

Once people are safe, decide how big the scene is. Look for where the incident started, how people got in and out, and where items may have been dropped. Then set a perimeter larger than you think you need. You can always make it smaller later, but evidence trampled outside a small perimeter is lost.

• Use tape, cones, doors or barriers, or stand in a spot where you can see the whole area.
• Allow one controlled path in and out, and keep it clear for paramedics and police.
• Keep everyone out who does not need to be there, including staff, managers and other guards.
• Inside the scene, do not eat, drink, smoke, use the phone or washroom, or change lights, heating or windows.
• Protect fragile evidence from weather and traffic, for example footprints in snow or marks that rain could wash away.

The scene log

Start a scene log as soon as you protect the area. Record every person who enters or leaves, the time in and out, and the reason. Paramedics and firefighters may need to enter to save a life; let them in and log them. If someone asks to enter and you refuse, write that down too.

If you must leave the scene for an emergency, hand it over to another guard or tell your supervisor first, and record the time and the reason.

Lesson 3: Types of evidence

Evidence is anything that can help show what happened. Knowing the main types helps you notice what to protect.

Witnesses are evidence too. Each person's account should be their own. If witnesses talk together, they may change what they remember without meaning to. Take their names and contact details, ask them to wait for police if they are willing, and do not tell them what you think happened.

Lesson 4: Handling, packaging and continuity

The best rule is simple: leave evidence where it is. Move an item only when it would otherwise be lost or destroyed, or when it is a danger to people, such as a weapon within reach of a crowd. Before you move it, note or photograph exactly where and how it was lying, if you safely can.

If you must collect an item

• Wear disposable gloves and handle the item as little as possible, by edges or areas unlikely to hold prints.
• Package each item separately so material cannot transfer from one item to another (cross-contamination).
• Use a paper bag or envelope for damp items such as blood-stained clothing, because plastic traps moisture that can damage evidence. Follow police directions if they give them.
• Seal the package and label it with the date and time found, the exact location, a short description, and your name.
• Keep the item secure and in your control until you hand it to police.

Continuity of evidence

Continuity (also called chain of custody) is a record of everyone who had an item, from the moment it was found until it reaches court. If there is a gap, a defence lawyer may argue the item could have been changed or swapped. When you hand an item to police, write down the officer's name and badge number, the time, and exactly what you gave them.

Lesson 5: CCTV and digital evidence

Video and electronic records are often the strongest evidence at a site. They are also easy to lose. Many recording systems record over older footage automatically after a set number of days, so act quickly.

1. Tell your supervisor or the person who manages the system that footage must be saved.
2. Note the cameras, dates and times that matter. Check the system clock against the real time and write down any difference, for example "system clock 4 minutes fast".
3. Export the footage using the site's approved method. Do not change camera settings or clocks unless your policy allows it.
4. Keep the exported copy unchanged. Do not crop, brighten or cut it. Record who exported it, when, and where it is stored.
5. Give it to police as your site procedure says, and record the hand-over.

Courts need to trust that electronic records are reliable. Under section 31.2 of the Canada Evidence Act, the best evidence rule for an electronic document can be met by proving the integrity of the system that recorded or stored it. Good records of who handled the footage help show that integrity.

Video also contains personal information. The federal Privacy Commissioner's video surveillance guidelines say footage should be used only for its stated purpose or as the law allows. Their example: footage of a car break-in can be shared with police, but parking garage video should not be used to track tenants. Never post footage online or share it with friends.

Lesson 6: Notes and hand-over

Write your notes at the time, or as soon as possible after. Include the time you arrived, what you saw, the people present, anything you moved and why, everyone who entered the scene, and when police took over. Courts may allow you, with the judge's permission, to refresh your memory from notes made close to the event, so accurate notes are worth the effort.

Scene protection checklist

• People are safe and 911 has been called.
• Perimeter is wide, with one controlled path.
• Scene log started and kept up to date.
• Fragile evidence protected from weather and traffic.
• Nothing moved unless necessary, and every move recorded.
• CCTV and other digital records flagged for saving.
• Witness names and contact details taken.
• Hand-over to police recorded, with officer name and badge number.