How long does private investigator surveillance take? There is no universal answer: a lawful surveillance engagement can run anywhere from a single shift to several weeks, depending on what the case needs to prove and how the subject behaves.
This guide explains what shapes a surveillance timeline, why a single day rarely settles a case, typical ranges by case type, and how a licensed Ontario investigator sets a realistic, honest timeline before work begins.
What Determines How Long Private Investigator Surveillance Takes
At Discreet Investigations, our PSISA-licensed investigators are led by Founder, President & CEO James Glanville, who has worked in the investigations field for more than 35 years since the firm’s founding in 1989. The firm is registered with the Ontario Solicitor General’s Private Security and Investigative Services Branch, and every investigator assigned to a surveillance file holds an individual licence under Ontario law.
That licensing background is what makes an honest answer possible. Timeline depends on the objective, not on a script: some cases resolve in a single shift, others take weeks to establish a clear pattern of behaviour. The factors below are what a licensed investigator actually weighs before giving you a working estimate.
- The case objective. A single documented event, such as a specific meeting, delivery, or outing, can sometimes be captured in one well-timed shift. Proving a repeated pattern of behaviour takes longer by definition.
- The subject’s mobility. A subject who keeps a fixed, predictable routine is easier to document quickly than one who travels widely or changes plans often.
- Traffic conditions and terrain. Dense urban routes, highway travel, and multiple destinations in a single day all add coordination time.
- Risk of detection. A subject who appears alert to being watched may require more careful staffing and additional observation windows to gather usable footage without compromising the file.
- Staffing level. Most shifts run with one to three investigators, scaled to the mobility, traffic, and detection-risk factors above.
For how a mobile surveillance assignment is actually conducted in the field, see our guide to mobile surveillance in Ontario.
Why One Day of Surveillance Rarely Settles a Case
By the firm’s own account, a single day is the exception, not the rule. Some cases resolve in a single shift; others take weeks to establish a clear pattern of behaviour. Most matters that turn on proving a repeated behaviour, rather than a single one-off event, need more than one observation window before the evidence supports a reliable conclusion.
That isn’t only a practical reality. It tracks the Office of the Privacy Commissioner of Canada’s Guidance on Covert Video Surveillance in the Private Sector, which requires a demonstrable, evidentiary need before covert surveillance is used, and limits collection to what is necessary to fulfill the identified purpose. A single unrepresentative observation rarely clears that evidentiary bar on its own, which is part of why investigators build in more than one observation window before drawing a conclusion.
There is also a quality dimension worth naming. A short window that happens to capture an unrepresentative moment can create a misleading record, and that is a different problem than simply running out of time. The strength of a surveillance file comes from whether the pattern it documents is representative, not from the number of days logged.
A pattern only becomes reliable once it repeats. A single observation, however clear, cannot rule out a coincidence, a one-off change in routine, or an exception to how the subject normally behaves. Repetition across separate observation days turns an isolated sighting into a documented pattern, which is why a licensed investigator rarely promises a conclusive result after only one shift.
Typical Surveillance Timelines by Case Type
Discreet Investigations frames the range by objective, not a fixed schedule. Whether a case calls for a short one-day operation or a multi-week pattern-of-life investigation, the firm scopes and delivers it. Surveillance teams also operate on a 24/7 basis, including evenings, weekends, and statutory holidays, so the case type and the subject’s own schedule set the working timeline, not a fixed business-hours model.
The ranges below are qualitative, not guarantees. Every case is scoped individually at the consultation stage, using the same objective, mobility, and detection-risk factors described above.
| Case type | Typical duration range |
|---|---|
| A single defined event (a meeting, outing, or delivery) | Often a single shift, occasionally extended into a second day if the event is rescheduled |
| Matrimonial or infidelity matters | Multiple shorter shifts across one to two weeks, timed to the subject’s known routine |
| Workplace or insurance-claim surveillance | Several observation days spread over one to three weeks, to capture a representative range of activity |
| Child custody or family matters | Multiple windows over one to three weeks, often timed around scheduled access or exchange days |
| Corporate or asset-locate investigations | One to several days at a single location, extending to multiple weeks when the subject or asset moves between locations |
Staffing scales with the case, not the calendar. Most shifts run with one to three investigators, depending on the subject’s mobility, traffic conditions, and risk of detection. A highly mobile subject, or one who appears alert to being watched, typically needs more coordinated coverage and more observation days to build a complete evidentiary picture. A case that combines several of these factors, such as a highly mobile subject in a multi-site insurance claim, typically lands toward the longer end of its range.
When to Extend Surveillance — and When to Call It
The decision to extend or end surveillance is itself governed by a proportionality standard, not open-ended discretion. The Office of the Privacy Commissioner of Canada’s guidance instructs organizations to limit the duration and scope of surveillance to what would be reasonable to meet their purpose. In practice, an investigator extends a window only as long as it takes to meet the case’s specific evidentiary objective. Surveillance stops once that objective, not an arbitrary day count, is met.
- Extend when the subject’s routine has not yet produced the behaviour the case needs to document, and there is a reasonable basis to expect it will.
- Extend when early footage is inconclusive, and a further window would resolve the ambiguity rather than simply add more of the same.
- Stop when the file already contains a representative, well-documented example of the behaviour in question.
- Stop when continuing would add burden and privacy intrusion without adding evidentiary value, the proportionality line the OPC’s guidance describes.
- Stop when the subject’s circumstances change in a way that makes further observation unlikely to add anything, such as a case resolving, an admission being made, or a claim being withdrawn.
Discreet Investigations frames this decision plainly: the firm gives clients an honest timeline at the consultation, and stops the moment the client has what they need. When a case runs longer than first estimated, a licensed investigator should explain why, in terms of the evidentiary gap still open, not simply request more time without a reason.
Setting a Realistic Timeline With Your Investigator
Only a PSISA-licensed investigator may lawfully set and run that timeline for hire in Ontario. Under Section 6 of the Private Security and Investigative Services Act, 2005, no person may act as a private investigator in the province without holding the appropriate licence. Section 45(1)-(2) sets offence penalties of up to $25,000, and up to one year’s imprisonment, for an individual operating without one, and up to $250,000 for a business entity. That licensing requirement matters here because an unlicensed operator carries no professional accountability if a promised timeline slips or a file is mishandled. A realistic timeline conversation should start with confirming the investigator’s licence status, not with a number of days.
Practically, that conversation is where the timeline gets set. The working range should come from the licensed investigator’s assessment of your specific case, not from a marketing promise of a fixed number of days. Our guide to what a first PI consultation covers walks through how that scoping conversation typically unfolds, including how to verify a licence before you commit to anything.
As licensed PSISA investigators in Ontario, we give an honest timeline at the consultation and stop the moment you have what you need. To talk through your situation, call +1 (888) 680-0036 or visit our surveillance services page.
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