What Does a Private Investigator Do? What They Can't Do

A private investigator (PI) gathers facts. People hire them to find out what is true, find someone, or collect evidence they can use in a legal case, a business decision or a personal matter.

TV makes private investigators look like they can do anything. In real life, licensed PIs work within clear legal limits. Knowing those limits helps you hire the right person and protects you from someone who would put your case at risk.

What does a private investigator do?

Most investigative work falls into a few categories.

Surveillance

Watching and documenting a person's activities in places where they can be lawfully observed, such as public streets, parking lots and businesses open to the public. Surveillance is used in insurance claims, custody disputes, workplace cases and suspected infidelity. The result is usually a written report with time-stamped notes, photos or video.

Background checks

Researching a person or business using public records and lawful databases: court cases, property records, business filings, licenses, and other records available to private investigators. People use these before a business deal, a hire, a large loan to someone, or a relationship decision.

There is an important legal limit. If a background report will be used to decide on employment, housing, credit or insurance, federal law (the Fair Credit Reporting Act) adds rules about permission and how the report is used. Ask the private investigator how they handle this.

Locating people (skip tracing)

Finding someone whose current address is unknown. This includes a person to be served with court papers, a witness, a debtor, a missing heir, or a lost family member or friend.

Infidelity and domestic matters

Gathering facts when someone suspects a partner is being unfaithful, or when a family law case needs evidence about a person's conduct or living situation.

Legal support

Helping lawyers with civil and criminal cases: finding and interviewing witnesses, gathering records, reviewing scenes, and preparing evidence for trial.

Business and insurance investigations

Employee misconduct, theft, fraud, workers' compensation claims and due diligence on companies or partners.

Digital and forensic work

Some private investigators specialize in recovering and analyzing data from devices the client has the legal right to access, or in reviewing public online information. This is a specialized field, and qualifications vary.

Yes or no: what people ask a private investigator for

Most first calls to a private investigator start with a request. Here are the common ones, with a straight answer to each.

"Can you watch where my spouse goes after work?" Yes. A private investigator can follow and film a person anywhere the public can see them: streets, parking lots, restaurants, store entrances. The work ends at the edge of private property they have no permission to enter.

"Can you get into his phone and show me who he's texting?" No. Logging in to another person's social media, email or phone without their permission is a federal crime, and so is pulling their phone records under false pretences. What a private investigator can do is document what that person does in public and check open sources.

"Can you record her conversations?" Not ones the private investigator is not part of. Federal law lets a person record a conversation they are in, and some states require every participant to agree. Planting a recorder to catch other people talking is wiretapping.

"Can you find out what's in his bank account?" Not by asking the bank while pretending to be him. Federal law specifically bans that trick. Assets can sometimes be traced through public filings, property records and court cases, and a court can order financial records produced in a lawsuit.

"Can you put a tracker on her car?" It depends on who owns the car and which state you are in. In many states it is a crime to track a vehicle you do not own without the owner's consent. Settle this with the private investigator, and ideally your lawyer, before anyone buys a device.

"Can you find someone who has moved and won't answer?" Usually, yes. Locating people (skip tracing) through public records and the databases licensed private investigators can use is everyday work.

"Can you talk to the neighbors?" Yes, if the neighbors are willing. Nobody is required to answer a private investigator's questions.

"Can you tell them you're with the police so they'll cooperate?" Never. A private investigator has no badge, cannot arrest, cannot stop cars and cannot demand ID. Claiming to be law enforcement is a crime.

"Will what you find hold up in court?" Often, if it was collected lawfully and documented properly, and the private investigator can testify about what they saw. Your lawyer decides what the case needs.

"What should I do about the case itself?" That is a question for a lawyer. Unless they are also a licensed attorney, a private investigator cannot give legal advice.

The short version

Think of a licensed private investigator as a skilled, patient member of the public with access to some extra databases. Anything you could not legally do yourself, they cannot do for you. Someone who offers to cross that line puts your case at risk: a judge can refuse to admit what they gathered, and you can end up facing a lawsuit or charges alongside them.

Do private investigators need a license?

Most states require private investigators to be licensed, and many require insurance, a background check and proven experience. A few states have no statewide license, and some regulate at the city or county level. Before hiring, check the license with the state agency that issues it. In Arizona, PIs are licensed through the Arizona Department of Public Safety. See our Arizona private investigator license guide.

How do I choose a private investigator?

• Verify the license with the state, not just the private investigator's website.
• Ask about experience with your exact type of case.
• Ask how they report. Written reports, photos, video, and whether they will testify if needed.
• Get the scope and cost in writing, including hourly rates, mileage and any retainer.
• Ask about confidentiality and how your information is stored.
• Be wary of guarantees. No honest private investigator can promise a specific outcome.

Frequently asked questions

Can a private investigator run a background check on a job applicant? Possibly, but employment screening has extra rules under the Fair Credit Reporting Act, including the applicant's written permission. Ask whether the private investigator works within those rules.

Do I need a private investigator or a process server? If you only need court papers delivered, a process server is usually faster and cheaper. If the person first has to be found, many private investigators do both.

Laws on recording, tracking and access to records differ from state to state. For advice about your own situation, talk to a lawyer.