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Mobile Surveillance with Two or More Private Investigators

Multiple (usually two) Private Investigators offer the ability to better control the surveillance environment, while better anticipating the subject’s movements in various scenarios. Furthermore, multiple Private Investigators lower “Heat” which allows closer surveillance of the subject with more regularity. One of the challenges that multiple Private Investigators can pose is logistics and communication during a surveillance operation.

The use of two or more Private Investigators takes the pressure off of what is normally accomplished with a single Private Investigator during surveillance. However, when a client authorizes a team of two or more Private Investigators for a surveillance operation, that client’s expectations are elevated along with their desire for results. So, on one hand the Private Investigators understand that a surveillance team is easier, if prepared. On the other hand, clients generally do not understand surveillance and with two or more Private Investigators they certainly do not want to hear “we didn’t get video” or “we lost the subject.”

Lead Private Investigator

The lead Private Investigator can be one of several things: the most senior Investigator, the manager of the specific surveillance file, or the Investigator with the visual of the subject. The later would, of course, alternate.

Filming Protocol

Filming, at one given time, is done by one Private Investigator unless specifically requested or the surveillance evidence is compelling enough to justify multiple angles to offer a wider range of information. This is done to avoid overlapping video, which is typically not wanted. To avoid this, it will be decided among the Private Investigators, who has the point or the eye and who will film at that time.

PI with slr camera

Surveillance Communication

Two-way radio

Two-way radios offer the ability for multiple Private Investigators to communicate instantly during surveillance. However, two-way radios can have poor range or limited battery life. Private Investigators typically find that two-way radios are not dependable during mobile surveillance, due to the ever-changing obstacles that interfere with the radio. Cellular service is available almost everywhere and very cost effective, making it the preferred communication tool for surveillance. Two-way radios are effective in areas where cellular signals are weak or not available. If required to use two-way radios, be equipped with extra batteries and a backup radio for each Private Investigator. If communication needs to be active and available at all times, the success of the surveillance file depends on the constant ability to communicate.

surveillance radio

Surveillance Communication Protocols

The Private Investigator with lead visual (The Eye) of the subject must communicate to the other Private Investigators key pieces of information while in active mobile surveillance. This includes,

· The compass bearing (north, south, east, & west)

· Street, Ave or Hwy name and or #

· Which lane (centre lane, middle lane, curb lane etc)

· Every cross street they cross

· The cross-street’s traffic control system, or lack thereof

· The colour of the traffic light and its freshness – when will it change and what is its current state.

· Speed

· The subject’s driving habits

· Confirm who currently has the eye – This practice should be communicated regularly as to not have other assume anything. The team needs to act and respond as one unit, if the surveillance is going to be highly effective.

· Future planned tactics

· Have the second Investigator(s) repeat back the statements. This insures the second Investigator correctly received the information and understands.

surveillance with two investigators using cell phones

Maintaining Surveillance

Maintaining Mobile Surveillance

Multiple Private Investigators allow for more avenues of travel to be covered during mobile surveillance, resulting in less potential for Heat. This is done by different Private Investigators positioning themselves for possible turns during surveillance. This way, the subject turns into a direction that an Investigator is already headed in vs changing direction with the subject. There is also the advantage of changing the Private Investigator who has lead visual or who might need to be directly behind the subject. This is typical in large cities with heavy traffic and congestion. This will allow the Private Investigator with the lead visual fall back out of view of the subject, reducing heat on them.

spy following a car on highway

Maintaining Static Surveillance

Multiple Private Investigators have the ability to cover more exit points on a given static surveillance location. This affords the ability for the Private Investigator with the lead visual to get closer to the subject, while other Investigators cover possible exit points. This also allows the Private Investigator with the lead visual to not have to immediately follow the subject out of the location, enabling the secondary Investigator to discretely maintain surveillance. This will reduce Heat and enable constant monitoring and more opportunities to document with video.

dark street

Client Perspective

Clients typically have high expectations of Private Investigators. With multiple Investigators on a surveillance file, that expectation is doubled. However, a well-functioning surveillance team of Private Investigators can fulfill the client’s higher expectations.


Having multiple Private Investigators on a surveillance file offers many advantages. Multiple Investigators can develop a pattern of the subject much sooner than an Investigator working alone. Furthermore, using more than one Private Investigator offers the chance to obtain more surveillance video evidence.

slr camera

Quick Subject Pattern Recognition

Two or more Private Investigators have a higher possibility of keeping constant visual of the subject during surveillance. Many instances, a single Private Investigator will temporarily lose visual of the subject or have to temporarily give up visual to lower Heat. This means that it can take a single Private Investigator more than one day to recognize a pattern.

white puzzle

Less Heat, More Video

There are many instances where a single Private Investigator will temporarily lose visual of the subject in order to lower, lesson, or manage Heat during surveillance. This can include letting the subject go when they enter a parking lot, or the area near their residence. The Private Investigator will then re-establish surveillance soon after. While this is beneficial in reducing Heat, the Private Investigator might have sacrificed opportunities to obtain video evidence in order to reduce possible Heat. Using multiple Private Investigators will increase surveillance continuity overall.

slr camera and laptop


There are many advantages in having a surveillance team of Private Investigators work on a surveillance file; however, there are a few disadvantages. If one of the Private Investigators is not skilled in working with a surveillance team this can reduce all of the investigative efforts. Keep in mind, the surveillance team is only as good as its weakest member.

chain with broken link
About the Author
Peter Sandru

Peter Sandru is an Instructor & Co-Founder of NDIL with over 15 years as a Professional Private Investigator. Peter has spent more than a decade conducting investigations and security operations throughout the world, primarily for corporations, law firms, and government agencies. Peter has assisted in the creation of numerous investigative & security training programs in various capacities. Peter has helped many individuals on their journey to becoming Private Investigators in Toronto.

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