When appropriate for the circumstances, we will often recommend GPS tracking to our clients.  Without fail, the most common response to this suggestion is some version of,

“Is that legal?”

The quick answer is usually, “Yes. Under these circumstances it is.” If I wasn’t as polite and reserved as I am, I would add, “I’m a police lieutenant with 25 years on the job.  Do you really think I’m going to jeopardize my career by doing something illegal for you?”

“Is GPS tracking illegal?” is actually a very good question to hear out of a prospective client, because it indicates to me that they are interested in staying on the right side of the law…and that is a place where I intend on staying.  The fact is, there are many circumstances where GPS tracking is clearly not legal.  At the same time, there are several situations where putting a GPS tracker on a vehicle is permissible under the law.  The laws regarding GPS tracking are complex (and gray in some instances).  The answer to the question usually can’t be given until we get answers to questions of our own (Who? What? Where? When? How? Why?).  And then the answer will usually be preceded by if, unless, as long as, or it depends on.  

I’m going to go over the questions we ask a client before we ever put a GPS tracker on someone’s vehicle as part of a case and then I’m going to give you some examples of when it might be okay for you to put a GPS tracker on a car, when you might want to hire a licensed P.I. to do it and some other situations where a GPS tracker would not be legal at all.

To start with, in many cases, the legality depends on answers to the following questions:

  • Where:
      • Where (geographically) is the GPS tracking being done?
      • Where is the vehicle going to be when the GPS tracker is mounted/retrieved?
  • Why:
      • Why is the GPS tracking wanted?
      • What is the purpose of the investigation?
  • Who:
      • Who is putting the GPS tracker on the vehicle?
      • Who is the Client?
      • Who is the person being tracked?
  • What:
      • What is the relationship between the person doing the tracking and the person being tracked?
  • How:
      • How is the GPS tracker mounted on the vehicle?
      • How is the GPS tracker powered?
      • How will the GPS tracker be installed?
  • When:
    • When will the GPS tracker be installed?

Where (geographically) is the GPS tracking going to occur?

First of all, there are not any Federal laws that make GPS tracking illegal, unless it is for law enforcement purposes (Law enforcement officers must always get a warrant to conduct GPS tracking).  However, there are several states that have implemented certain statewide restrictions on GPS tracking for non-law enforcement purposes.  

  • Most states have not specifically addressed the issue of GPS tracking.  
  • In some states, the issue has been specifically addressed and they have passed laws allowing virtually no GPS tracking (with the exception of law enforcement with a warrant).  
  • In other states, the issue has been addressed and they’ve determined that GPS tracking is allowed, but that the person placing the tracker must be the registered owner of the vehicle on which the tracker is being placed.  
  • In still other states, they have determined that GPS tracking is not allowed unless you either own the vehicle, or you have hired a licensed P.I. who has a permissible purpose to place the tracker on the vehicle.

And then there is the issue of where the vehicle is when the tracker is installed on the vehicle.  This is mainly an issue of whether a private investigator is trespassing on private property when he installs or removes the tracker.  Trespassing is defined in different ways in different jurisdictions.  In most jurisdictions, one is not trespassing unless the property is either posted, “No Trespassing” or until the person has been told to leave the private property.  There are other considerations also.  For instance, a P.I. wouldn’t enter a garage or a fenced in area in order to install a tracker, however if he had permission of the owner of the property, this would be okay.  

The most common place that P.I.’s install trackers is when the subject is out and about in their vehicle.  For instance, when the subject drives to the grocery store and parks his vehicle in the parking lot.  As soon as the subject goes inside the store, the investigator might pull up next to the vehicle and install the tracker.

Why? or What is the Purpose of Tracking the Vehicle?

Now, this isn’t a question that we will typically have to come right out and ask, as it usually becomes evident early on in the discussion when someone calls our office.  But it is important to be able to articulate why we are putting a tracker on a vehicle.  In the private investigation business, we have a duty to make sure that we have a permissible purpose before we do any investigation for a client.  This means we have to make sure that there is a legitimate and legal reason for wanting to know the information.  For example, if a man called our office and said he wanted a GPS tracker placed on a certain female’s vehicle.  We would not just go and put the tracker on the vehicle without knowing who that woman is to him and why he wants to know where she is going.  Just like we wouldn’t give him information on who a vehicle was registered to unless we knew why he wanted the information.  As a licensed private investigator, we have a duty to ensure that he’s not a stalker or a jealous ex-boyfriend and that he has a legitimate reason for wanting to track this person. Additionally, we would definitely run a criminal history check on the prospective client as well as determine if he had any history of violent or suspicious behavior.

Reasons that a P.I. Would Put a Tracker on Someone’s Vehicle

  • Suspicions of infidelity in a relationship (as long as there are no reasons to believe the client might hurt the subject…. Or that there are no TPO/TRO’s in place)
  • Suspicions that a previous salesperson is violating a noncompete agreement and you want to see if he is trying to steal your business.
  • Your daughter’s husband just beat the crap out of your daughter and she has filed domestic violence….
  • You have reason to believe that your ex-husband is leaving your 4-year old son home alone while he goes out drinking with his buddies during his visitation weekend.
  • You are considering asking your girlfriend to get married, but you have concerns recently that she is seeing her ex-boyfriend behind your back.
  • You’re worried that your ex-wife is going to skip town with your children and you want to know where they end up.
  • You’re worried about your father who is in the early stages of dementia and sometimes gets lost when he goes for a drive in his vehicle.
  • You’re concerned about where your juvenile son is going with your car, how fast he is driving and worried about his general safety while out and about.

Reasons that a P.I. Would NOT Put a Tracker on Someone’s Vehicle

  • You saw a hot girl at the gym and you are interested in who she is, where she works and what her daily activities are.
  • You are wondering why your neighbor suddenly leaves his house at midnight every evening and doesn’t return until 3am.
  • You are wondering who your ex-wife is dating because you are still obsessed with her.
  • You have a court-ordered protection, restraining or anti-stalking order against you.
  • We, as the private investigator, just have an odd feeling about the client.

Who is Doing the GPS Tracking?

Law Enforcement, the 4th Amendment

and Covert GPS Tracking

Up until 2012, law enforcement officers (local police, FBI, DEA, etc) were allowed to use GPS trackers as freely as anyone else.  However, in that year, the Supreme Court ruled that the government and law enforcement agents are not permitted to install GPS devices on someone’s vehicle unless a signed warrant is first obtained by a judge. The Supreme Court did not specifically address whether it is legal or illegal for a private citizen to track another person, vehicle, or property, but some state courts have ruled on the non-law enforcement aspect of GPS tracking with varying results.  


Much of this topic goes back to “permissible purpose” and why the client wants tracking done.  

Only a handful of state courts have specifically addressed the issue of GPS tracking.  As far as what the state courts have determined, it is generally okay to put a GPS on a vehicle that is registered to you.  In most cases, this would extend to a vehicle listed in a spouse’s name, which would be considered “community property.” However, there are states where it is illegal for anyone to put a GPS tracker on anyone’s vehicle, including their own.  

The next question is whether the person wanting to install a tracker is the registered owner of the vehicle.  This is only a factor if you are doing your GPS tracking in the handful of states that have determined it to be illegal for anyone, including P.I.’s to use GPS trackers in their jurisdictions (Of course, law enforcement can use GPS trackers in any state, as long as they have a court order).

In most states, a non-licensed P.I. could put a tracker on his own vehicle, or his wife’s vehicle vehicle for that matter (unless a protection or restraining order is in place against him).  However, he would not be allowed to put a tracker on his girlfriend’s car (unless he actually owned the vehicle or it was registered to him).  At the same time, in some states, he could legally hire a licensed private investigator to put a GPS tracker on his wife’s car or his girlfriend’s car, regardless of who owns the vehicle.

What is the relationship between the person doing the tracking and the person being tracked?

Are they married? Are they divorced or separated? Are they in business together? Again, if the person who is doing the tracking owns the vehicle, they are usually going to be okay putting a tracker on the vehicle.

Why is it legal for a P.I. to put a tracker on a vehicle but I can’t do it myself?

What’s the difference, you might ask? Why can a licensed P.I. put a tracker on my girlfriend’s car, but I can’t.  The answer comes down to the issue of stalking.  

Stalking: A pattern of conduct that includes following,

harassing, or threatening another person.

In order to become a licensed private investigator in most states, one has to first pass background investigations by the state law enforcement and the FBI.  Additionally, most states also require that private investigators pass a written test that ensures they have an understanding of criminal and civil laws, including laws regarding privacy and when it is permissible to watch or video record someone’s activities.

Stalking versus Investigating

A P.I. license is what makes it okay for the private investigator to sit in his car and video record a person he’s investigating.  It also makes it okay for him to surreptitiously follow someone (shadow) around as they go about their daily activities.  These activities would be considered stalking were the private investigator not licensed and carrying out his work with a permissible purpose.

Once an investigator is clear that a permissible purpose exists to put a GPS tracker on a vehicle, most responsible private investigators will take the step of ensuring that there aren’t any court-imposed restraining or protection orders in place.  A reputable and responsible investigator won’t put a GPS tracker on a vehicle if there is any kind of history of domestic violence, either.

In recent years, most states have applied and extended their current stalking laws to the use of GPS tracking and this approach actually makes sense.  

More Common GPS Scenarios & Twists

Suspicious Workers Compensation Claimant; Let’s say an employer has an employees who is out of work on a disability/workers’ compensation claim that restricts the worker from lifting anything over 10 pounds or doing anything physically strenuous.  Now, let’s say that the employer receives information that this “injured” employee is an avid power lifter and is training hard at the local gym.  It would not be legal for the employer to go out and put a GPS tracker on the employee’s vehicle, because that would qualify as stalking (unless the vehicle was registered to the employer).  However, in most states, the employer could hire a private investigator to put a GPS tracker on the employee’s vehicle to investigate whether they are being defrauded by the employee.

Infidelity (Married); In most situations, a person can put a GPS tracker on their own car, or their spouse’s vehicle.  A licensed private investigator is not usually necessary in this type of situation.  However, if the couple is separated, or if there is some sort of court order in place (Protection Order, Restraining Order, Anti-Stalking Order), it would not be a good idea for anyone (including the P.I. to put a tracker on the vehicle).  

Infidelity (Unmarried); Let’s say that a woman believes that her fiancé is screwing around with his ex-girlfriend and she wants to find out if he is being truthful with her or if he is cheating on her.  In this case, the woman would not be legally permitted to place a GPS tracker on her fiancé’s vehicle unless the vehicle was registered to her (or, unless he gave her permission…not!).  However, in most states, she could hire a licensed private investigator to place a GPS tracker on the vehicle as the P.I. would be using the tracker as a tool to investigate and gather due diligence for his client since the client is about to enter a into a contract (marriage) with the man.  

Child Custody: A common concern is when a parent believes that the other parent is acting irresponsibly, illegally or in some way endangering their children.  You would not be allowed to put a tracker on your ex-spouse’s vehicle (or a vehicle belonging to anyone not belonging to you or your current spouse), however, in most cases, you would be able to hire a licensed P.I. to

Theft Investigation: If you believe that someone is stealing from you or your business/company, you would not be allowed to place a GPS tracker on their vehicle, however, in most states, you would be allowed to hire a licensed P.I. to place a tracker on their vehicle.  This scenario get’s a bit more complex if you uncover that a crime is actually taking place as a result of your GPS tracking/investigation and you decide to involve law enforcement in the situation.  Now, you or your P.I. would be allowed to share what you’ve discovered with the police, but if the police wanted to move forward with their own investigation, they would have to get a court-ordered warrant to continue any GPS tracking since this is now a law enforcement investigation.

When it is legal for a P.I. to do the tracking vs a Non-P.I.?

Basically, if the vehicle does not belong to you, you cannot personally put a tracker on the vehicle.  However, in most states, it would be legal for a licensed private investigator to place a GPS tracker on a vehicle, as long as he has a permissible purpose (good reason) to do so.  

How is the GPS tracker mounted on the vehicle?

Here is what the courts have generally determined.  If you own the vehicle, you can install a GPS tracker on that vehicle and have it powered off of that vehicle.  However, if you hire a P.I. to surreptitiously install a GPS tracker on a vehicle that you don’t own, that GPS tracker cannot be powered off of the vehicle.  The unit must be powered independent of the vehicle’s power.  Some GPS trackers have internal batteries and some have to be hooked up to an external battery.  

Independent, battery-powered GPS units can run anywhere from two days, up to 6 months, depending on factors such as amount of driving/movement, GPS reception, weather and size and age of the battery.

How will the GPS tracker be installed?

Most of the time, a GPS tracker will be installed on the outside of a vehicle, underneath the vehicle.  It only takes a moment for to place the vehicle under the car and it is usually attached by a magnet.

I hope that I’ve answered most of your questions about GPS trackers.  If you have any further questions, please give us a call and we’ll do our best to answer your questions.  If we don’t know the answer, we’ll find it out for you.

Disclaimer: Just to be clear, I am a licensed private investigator in California, Ohio and New York.  I am not a lawyer and do not offer legal advice.  If you have a legal issue, you need to speak to a lawyer.

The goal of this site is simple; to be the most-trusted and best source of information about every aspect of private investigators and private investigations, whether you are looking to do your own private investigation or considering hiring a private investigator Paul Baeppler is currently a full-time police lieutenant with 25 years on the job. He also runs several private investigation and security businesses, licensed in Ohio, California and New York. www.clevelandprivateinvestigator.com www.manhattaninvestigations.com