Hiring a private investigator for divorce makes sense when contested issues around custody, support, or hidden assets turn on evidence you can’t gather yourself. A licensed PI can run surveillance, trace undisclosed money, document a parent’s behavior during custody time, and pull together a digital record that holds up in family court. Surveillance typically runs $85 to $150 per hour, with retainers starting around $1,500 for straightforward cases. The work is legal when done correctly, but investigators who cut corners can tank your case and expose you to liability alongside them.
What a Private Investigator Can Do for Your Case
Surveillance and Cohabitation
Physical surveillance is the core assignment: where your spouse goes, who they spend time with, and whether their day-to-day life matches what they’re telling the court. This matters most when one spouse is receiving alimony while living with a new partner. In many jurisdictions, proof of cohabitation can reduce or terminate spousal support, and investigators build that proof by documenting overnight stays, shared groceries, joint mail retrieval, and the other small signals that two people are running a household together. A few weeks of documented patterns can save a paying spouse years of unnecessary support.
Hidden Asset Discovery
Financial investigations go well beyond a basic bank search. Investigators trace undisclosed accounts, real estate held through shell companies, and lifestyle spending that doesn’t line up with reported income. They review bank and brokerage statements for transfers to cryptocurrency exchanges, then use blockchain analysis to follow funds through digital wallets, decentralized finance platforms, and token swaps. That kind of tracing has become essential as more wealth moves into digital assets that never show up on traditional financial statements. What the investigator finds feeds directly into child support calculations and property division.
Child Custody Investigations
When a parent’s fitness is in dispute, an investigator can observe what actually happens during custody time. They note heavy drinking, children left unsupervised, or exposure to unsafe people or environments. They verify compliance with court orders like supervised visitation or right-of-first-refusal clauses. Timestamped video and detailed activity logs carry far more weight than one parent’s word against the other, and they give a judge something concrete when deciding what arrangement serves the child’s best interests.
Social Media and Digital Footprints
Social accounts are often the first place an investigator looks, and the results can be devastating to the other side. A spouse claiming financial hardship while posting vacation photos. A parent seeking custody while sharing pictures of heavy partying. A partner denying a new relationship while tagged in a significant other’s posts. Investigators also review posts from friends and family that may reveal information your spouse tried to keep private. None of this requires hacking. Public posts, check-ins, and tagged photos are fair game and regularly end up as exhibits in family court.
Legal Limits a PI Cannot Cross
The line between aggressive investigation and criminal conduct is well-defined, and crossing it can destroy your case while creating new legal problems for you personally.
Wiretapping and Eavesdropping
Federal law prohibits intercepting phone calls, emails, or other electronic communications without proper authorization. An investigator cannot install a hidden microphone, use spyware to capture text messages, or record private phone conversations. Violations carry penalties of up to five years in federal prison.1Office of the Law Revision Counsel. 18 USC 2511 – Interception and Disclosure of Wire, Oral, or Electronic Communications Prohibited Some states require all parties to a conversation to consent before recording, which further limits what an investigator can capture even when they’re physically present.
Unauthorized Computer Access
The Computer Fraud and Abuse Act makes it a federal crime to access a computer or online account without authorization. An investigator who guesses a password, exploits a saved login, or bypasses security to read a spouse’s email or bank statements is committing a felony. First-time violations can carry up to five years of imprisonment when the access furthers a criminal or tortious act, and repeat offenses carry up to ten years.2Office of the Law Revision Counsel. 18 US Code 1030 – Fraud and Related Activity in Connection With Computers Being married to the account holder is not an exception.
GPS Tracking
Placing a GPS tracker on a spouse’s vehicle sits in a legal gray area that varies by state. At least nine states specifically prohibit installing a tracking device on a vehicle without the owner’s consent, and six states have broader laws prohibiting electronic tracking of a person’s location without consent. Florida’s statute is particularly relevant to divorce: consent to tracking is presumed revoked once either spouse files for dissolution of marriage or a protective order.3National Conference of State Legislatures. Private Use of Location Tracking Devices State Statutes Even on a jointly titled vehicle, assume tracking without explicit consent is illegal in your state unless an attorney tells you otherwise.
Trespassing and Trash
Investigators cannot enter a locked home, climb fences, or trespass on private property to take photographs. Legitimate surveillance stays in public spaces where no one has a reasonable expectation of privacy. Trash is a narrower question. The Supreme Court held in 1988 that garbage placed at the curb for collection is not protected by the Fourth Amendment, because the person discarding it has no reasonable expectation of privacy in it.4Justia US Supreme Court. California v Greenwood, 486 US 35 (1988) Some local ordinances still restrict dumpster diving, and retrieving trash from within private property rather than the curb can still be trespass.
Why You Share the Risk
Hiring the investigator doesn’t insulate you from what they do. This is where people get blindsided, and it’s worth understanding before you sign a retainer.
If an investigator trespasses, records conversations illegally, or hacks into accounts while working your case, you can face civil liability alongside them. Courts have held that when a client directs or knowingly benefits from an investigator’s illegal methods, the client shares responsibility for the resulting harm. Even without an explicit instruction to break the law, a court may conclude you should have known the methods were improper, especially when the results could only have come from unauthorized access.
The consequences follow you into the divorce itself. Judges scrutinize how evidence was obtained, and improperly gathered material can be excluded entirely. Federal wiretapping law specifically bars illegally intercepted communications in both criminal and civil proceedings, so recorded phone calls obtained without proper consent are typically thrown out even in family court. Worse, trying to introduce tainted evidence can undermine your credibility on every other issue. The spouse who hired someone to illegally access an email account rarely comes out looking like the reasonable party in a custody fight.
Getting the Evidence Into Court
Raw footage and photographs don’t walk themselves into evidence. The investigator’s work product has to clear specific procedural hurdles before a judge will consider it.
Authentication
Under federal evidentiary rules adopted in some form by every state, anything offered as evidence must be shown to be what the offering party claims. The usual method is testimony from a witness with personal knowledge: the investigator takes the stand and testifies that they personally captured the footage, when and where they recorded it, and that it hasn’t been altered.5Legal Information Institute. Federal Rules of Evidence Rule 901 – Authenticating or Identifying Evidence Without that testimony, a video file is just a digital file with no verified connection to the events it supposedly shows.
Hearsay
Written investigation reports face a separate challenge. Because they contain out-of-court statements, opposing counsel will often object that they are hearsay. The workaround is simple: the investigator must be available for cross-examination. When they can testify in person about what they observed, their report supports rather than replaces their testimony. Courts treat a report backed by live, cross-examined testimony very differently from one submitted on its own.
Exclusion of Illegally Obtained Evidence
The constitutional exclusionary rule that suppresses evidence in criminal cases generally does not apply in civil proceedings, including divorce. That doesn’t mean anything goes. Federal wiretapping law and the Computer Fraud and Abuse Act both contain their own provisions barring admission of evidence obtained through violations of those statutes, and many state wiretapping laws mirror that approach. A photograph taken from a public sidewalk will survive even if the subject feels their privacy was invaded; a secretly recorded phone call almost certainly won’t.
What It Costs and How Long It Takes
Most investigators charge hourly for surveillance, with standard rates between $85 and $150 per hour in most markets. Complex financial investigations, particularly those involving cryptocurrency tracing or offshore accounts, run higher. Expect to pay a retainer of $1,500 to $5,000 before work begins, depending on complexity. If the investigator needs to testify, appearance fees typically run $150 to $300 per hour plus preparation time, and a full day of expert testimony can cost $1,000 to $2,500.
Straightforward surveillance can produce useful results in a matter of days. Establishing a documented pattern of behavior, which is what most custody and cohabitation cases require, typically takes several weeks of intermittent monitoring. Financial investigations involving hidden assets or cryptocurrency tracing can stretch to several months, especially when subpoenas to exchanges and financial institutions are involved.
What to Give Your Investigator Up Front
The more you supply at the start, the faster and cheaper the investigation. At minimum, expect to provide:
- Full legal name, recent photograph, physical description, and any known aliases
- Vehicle year, make, model, color, and license plate number for mobile surveillance
- Daily routine: workplace address, typical hours, gym schedules, recurring appointments
- Recent tax returns, insurance policies, bank statements, and property records you can access from shared files
- A clear statement of what you believe is happening and why, so the investigator can focus their time on the right questions
Most firms require a signed retainer agreement before beginning work. Some also require a written statement explaining your purpose for the investigation.
Choosing a Licensed Investigator
More than 40 states and the District of Columbia require private investigators to hold a license. A handful of states, including Alaska, Idaho, Mississippi, and Wyoming, have no state-level licensing requirement, though local regulations may still apply. Licensing typically requires a background check, proof of relevant experience, and in many states passage of an examination.
Before you hire anyone, verify their license through your state’s regulatory agency. Most states maintain online searchable databases where you can confirm license status, check for disciplinary actions, and see whether credentials are current. An unlicensed investigator’s work product is vulnerable to challenge in court, and judges in family cases tend to look skeptically at evidence gathered by someone operating outside the law.
Beyond the license, look for investigators who carry professional liability insurance, sometimes called errors and omissions coverage. A firm with adequate insurance protects you if their work causes harm or leads to a legal dispute. Ask whether they have specific experience with family law. Divorce investigations involve unique constraints around spousal privacy, shared property, and child safety that a corporate fraud investigator may not know well. The Certified Legal Investigator designation from the National Association of Legal Investigators requires at least five years of full-time investigative experience and passage of written and oral examinations, which signals a level of specialization worth seeking out.