What Methods Do Private Investigators Use?

You may find yourself in a situation where it’s necessary to file a claim. Maybe you’ve been discriminated against at work, or you suspect a spouse may be cheating. Injustices are committed every day against innocent, well-meaning people. Often, such cases don’t merit a full-blown police investigation—perhaps they’re more civil in nature. Nevertheless, you need an advocate, someone to do the legwork that will aid a lawyer in building a case against your offender. In other words, it might be time to hire a private investigator.

When to Consider Hiring a PI

Say the injustice being committed is criminal in nature. If so, a private investigator, also known as a “PI”, will support the work law enforcement is already doing, and in many instances, the evidence a PI collects will expedite a claim that may otherwise have lagged in court. It is common knowledge that, in California, as in many places, law enforcement is already stretched thin, making a private investigator an excellent option for helping bring about the right outcome.

As you can imagine, a private investigator has many techniques and methods for collecting the most vital of assets: evidence. The stronger the evidence—that is, the more irrefutable in court—the stronger the claim. A client may know in their heart that they are being discriminated against, for example, but without provable evidence, they may not receive the justice they deserve.

Additionally, a client should always choose a reputable firm with lots of experience to conduct a private investigation—an agency that works with a full range of people involved in any search for justice, from families, individuals, governmental bodies, businesses, and insurers. Hiring a private investigator is no small decision, and you owe it to yourself to find one that utilizes all the tools that modern technology offers. The methods detailed in this post are only a sampling of what is out there.

How Do PIs Do Surveillance?

Private investigators don’t just conduct surveillance on TV. It’s often a necessary part of a real-life investigative effort. Evidence is information, and a fundamental way to gather information is to observe. PIs have at their disposal many ways to do this, from simply following a person of interest and taking notes, to utilizing image-and-sound-capturing technology like cameras, audio recorders, and wiretaps. Surveillance is a broad subject in the world of civil and criminal investigations, and it seemingly changes by the day. Here is an overview.


Closed-circuit cameras are everywhere these days. An investigator on retainer with either a law firm or even a private client can often gain access to a business’s recorded video. And given that all footage is now digital, it’s easier to pinpoint the section of video most vital to a case.


Of course, there’s also traditional hand-held camera work, whether it involves a video camera or a DSLR (digital single lens reflex) with a powerful zoom lens. Private investigators have been using cameras to gather evidence for nearly as long as the camera has been around.

GPS Tracking

GPS can be used for evidence involving motor vehicles, whether it is to track the movements of a spouse suspected of cheating or the whereabouts of a convicted drunk driver. A potential drawback of installing a GPS tracker on a vehicle, however, is that permission must be granted by the owner of the vehicle for the evidence to be upheld. Nevertheless, GPS tracking can be useful under the right circumstances.


Spyware installed on personal computers, laptops, and cell phones can be used to extract information in real-time, but the evidence is not always admissible in court. Under the right circumstances, as with GPS tracking, spyware can be a valuable tool in a PI’s arsenal.

Technologies Requiring Consent

Technologies that require consent, such as GPS tracking, spyware, and the long-utilized and somewhat famous technique known as wiretapping, shouldn’t be ruled out. As an example, take a client who suspects an insurance company of fraud—depending on where the claim is based, it may be legal for that client to allow an investigator to tap his phone line.

In California, however, wiretapping requires the consent of both parties involved, so the technique may not be as useful there. It should be noted, though, that in California, it is legal for law enforcement to use a wiretap in a criminal investigation. That leeway can be granted to a licensed private investigator, as well, dependent on the case.

Can Private Investigators Spy on Cell Phones?

In some states, the answer is no. In others, it may be legal, but it is strictly regulated and allowed only for detectives and licensed private investigators. So the answer to the question above is yes, but not always.

Special Databases

Multiple online databases are available to investigators. In fact, several of them are only available to law enforcement and private investigators. Sites such as Enformion, Tracers, and Datalink offer location services. Some, like Locate Plus, specialize in skip tracing, the practice of locating individuals who have “skipped” town for some reason or other, usually a failure or outright refusal to meet a financial obligation.

Speaking of financial obligations, private investigators have also been known to utilize credit monitoring agencies, like Experian and Equifax, to gather evidence.

The databases listed above make up a fraction of those available to investigators. There are, quite literally, dozens more. Some require a monthly fee, others do not. It stands to reason, though, that those requiring a subscription likely provide the most thorough leads. And if the information is consistently accurate and reliable, then the investigative agency probably considers the monthly fee a worthwhile cost of doing business.

Device Cloning

Technology has made investigative work much more efficient. It has also made it easier for a PI to remain undetected. There is software, for example, that will allow an investigator to clone the data from a target’s cell phone without ever having to touch the actual phone. Such software allows a PI to view incoming calls and text messages as if they were being delivered to their own phone.

This technology also exists for the cloning of hard drives from both desktop computers and laptops. While carefully planning out their major steps, fraudsters are often surprisingly sloppy in the details, and they may unwittingly leave valuable information on a device just waiting for the right investigator to come along and extract it by way of cloning. It should be noted, however, that practices such as these may be restricted by law.

Background Checks

When it comes to the methods available to private investigators, background checks enjoy nearly as much notoriety as surveillance and wiretapping. Indeed, background checks are the heart and soul of many private investigation firms. In the public imagination, background checks are associated with landing a job, getting married, earning credit, and more. It’s no stretch to say a less than ideal candidate for a job might dread the much-touted, ubiquitous background check. It’s even less of a stretch to say that a suspect accused of insurance fraud might wish to avoid a process that will uncover past misdeeds. After all, a background check may very well reveal a criminal history.

How Much Does a Private Investigator Cost?

When determining the cost of a PI, you must consider a few factors. Like lawyers, PIs will often charge an hourly rate. Depending on experience and success rate, fees can range between $50 and $300. Also, like lawyers, PIs may sometimes provide their services on retainer, meaning, for an initial, agreed-upon payment. Again, dependent on experience and rate of success, an investigator will pull from that sum as needed rather than keeping track of working hours.

Some investigative services, like background checks or sweeps for surveillance devices in a house or business, are more defined and therefore require only a one-time payment. In other words, the private investigator knows upfront the amount of work involved and will charge a set price for that specific job.

The Discipline of Private Investigation

When done well, the discipline of private investigation is something of an art. It certainly is far more nuanced than what can be captured in a blog post. This rundown of methods and techniques is meant to get the conversation started—a conversation that you will hopefully continue with a proven firm like Amatrix Investigations. We believe that if you are researching investigative methods, it could be that you are in need of a reliable and results-driven private investigator. Our practice covers a wide range of areas: civil and criminal cases; adult and juvenile cases; cases involving family law; cheating spouses; insurance fraud—you name it.

As a result of rapidly developing technologies, investigative practice is ever-changing. At Amatrix Investigations, we actively pursue those methods that will yield the highest rate of success. If you want to learn more about the techniques a private investigator relies on, we invite you to contact our office. Our extensively experienced and well-trained staff are knowledgeable about up-to-date techniques and methods utilized in private investigation today.

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