A Special Investigations Unit, or SIU, is the team inside an insurance company that investigates claims the insurer suspects may be fraudulent, exaggerated, or fabricated. If you’re asking what an SIU in insurance is because your own claim was referred to one, it means an adjuster or an automated system flagged something worth a closer look before the insurer decides to pay, adjust, or deny. Being referred isn’t the same as being accused, but how you respond matters, because the process carries real consequences at every stage.
Why Claims Get Referred to an SIU
Not every claim reaches an SIU investigator. Most start with an adjuster or a predictive scoring system that spots something inconsistent with a routine loss. Common triggers include a claim filed shortly after a new policy was purchased, a history of frequent similar claims, repair or medical estimates that seem disproportionate to the incident, conflicting witness statements, or a claimant who refuses to provide basic documentation.
Modern SIUs also lean heavily on predictive analytics. Insurers score incoming claims against thousands of data points, and a claim that looks unremarkable on its own can score high because it shares characteristics with previously confirmed fraudulent claims in the insurer’s database. The algorithm flags it, and a human investigator decides whether to open a full inquiry.
SIUs generally sort what they find into two categories. Hard fraud is deliberate and premeditated: staged collisions, arson for the payout, fabricated thefts. Soft fraud is opportunistic padding of a real loss, such as inflating a repair estimate or adding items to a theft claim that were never stolen. Soft fraud is far more common, and it can still lead to claim denial, policy cancellation, and in many states criminal prosecution.
What an SIU Investigation Actually Involves
Once a claim is assigned, the investigator’s job is to test whether the story holds together from every angle.
Interviews and Records
Expect the investigator to interview you, any witnesses, and service providers such as body shops, contractors, or medical offices. Investigators also pull financial records, phone logs, and social media activity looking for contradictions. A claimant who reports a debilitating back injury but posts photos of a weekend ski trip is the kind of inconsistency that turns a routine review into a serious investigation.
Surveillance is another tool, though it comes with legal limits. Investigators can generally observe and record activity in public spaces; those limits tighten sharply on private property.
Forensic Analysis
For property and auto claims, physical evidence often tells a clearer story than interviews. Fire investigators examine burn patterns and test for accelerants. In auto cases, reconstruction specialists analyze vehicle damage, skid marks, and event data recorder information to see whether the reported collision matches the physics of what happened. EDR data is especially useful because it objectively captures vehicle speed, braking, and impact severity in the seconds before a crash.
Medical claims get their own forensic scrutiny. Investigators review billing records for upcoding, where a provider bills for a more expensive procedure than what was performed, and phantom billing, where services were never rendered. Independent medical evaluations may be ordered to verify whether reported injuries match the clinical evidence.
Cross-Company Databases
Insurers share claims data with each other. The National Insurance Crime Bureau partners with member insurance companies and law enforcement to identify patterns of suspicious claims,1National Insurance Crime Bureau. Your Trusted Partner in Leading the Fraud Fight and NICB alerts feed into ISO ClaimSearch, which tracks claims history across auto, property, and casualty lines.2National Insurance Crime Bureau. Member Benefits Your current insurer can see whether you’ve filed similar claims with other companies, whether a vehicle has a theft or salvage history, and whether the same addresses or phone numbers keep appearing across unrelated claims.
Your Rights and the Insurer’s Limits
Investigating fraud does not give an insurer a blank check to comb through your personal life. Federal and state laws set boundaries.
The Fair Credit Reporting Act requires insurers to have a permissible purpose before pulling a consumer report, which can include credit history, driving records, and medical information. For reports containing medical information, the insurer must get your consent before a consumer reporting agency releases it. If the insurer takes an adverse action based on a consumer report, such as denying a claim, it must notify you and identify the agency that provided the information.3Federal Trade Commission. Consumer Reports: What Insurers Need to Know
The HIPAA Privacy Rule adds a separate layer for health information. Covered entities generally cannot use or share your health information without written authorization unless the disclosure fits an exception like treatment, payment, or health care operations. An insurer can use your health data to process and pay your claim, but sharing it beyond that scope requires your permission or a legal basis such as a subpoena.4U.S. Department of Health and Human Services (HHS). Summary of the HIPAA Privacy Rule
Every state also has unfair claims practices laws that prevent insurers from using investigations to delay or deny legitimate claims. These typically prohibit failing to investigate promptly, refusing to pay without a reasonable basis, and dragging out the process to pressure claimants into accepting less. Violating those standards can expose the insurer to regulatory penalties and, in most states, bad faith lawsuits. A finding of bad faith can let the policyholder recover consequential damages, emotional distress, attorney’s fees, and in some cases punitive damages.
The Examination Under Oath
If an investigation escalates, you may be asked to sit for an Examination Under Oath, commonly called an EUO. This is one of the most consequential steps in the process, and most people don’t see it coming.
An EUO is a formal sworn proceeding where the insurer’s attorney questions you about your claim while a court reporter transcribes every word. It carries the same legal weight as courtroom testimony, and lying during an EUO constitutes perjury. It’s a fundamentally different experience from the recorded statement you may have given right after filing. A recorded statement is usually an informal phone call with an adjuster. An EUO is an in-person legal proceeding run by a lawyer whose job is to protect the insurance company’s money.
You have the right to bring your own attorney, and doing so is almost always worth it. Your attorney can object to improper questions and advise you during the proceeding. Submitting to an EUO is typically a condition of your policy’s cooperation clause. Refusing to appear, or appearing and refusing to answer, gives the insurer grounds to deny your claim entirely, and courts have consistently upheld denials on that basis.
How an SIU Investigation Can End
The outcome depends entirely on what the evidence shows.
Claim Approved or Adjusted
If the investigation turns up no fraud, your claim proceeds normally and the insurer pays according to your policy. In many cases the SIU finds minor discrepancies that don’t amount to fraud: a billing error from a medical office, an inflated repair estimate, a miscommunication about the scope of damage. The insurer may adjust the payout and request additional documentation, but the claim itself isn’t denied.
Claim Denied and Policy Cancelled
When the evidence points to intentional fraud, the insurer denies the claim outright. Depending on severity, it may also cancel or non-renew your policy. A fraud-related cancellation becomes part of your insurance history and makes future coverage substantially harder and more expensive to get. Other insurers will see the cancellation through industry databases, and many will decline to write a policy at all.
Criminal Referral
SIUs cannot arrest anyone or file charges. What they can do is package their evidence and refer it to law enforcement or a state fraud bureau. Under federal law, insurance fraud involving false statements to regulators or embezzlement from an insurer carries up to 10 years in prison, or up to 15 years if the fraud threatened the insurer’s solvency.5Office of the Law Revision Counsel. 18 U.S. Code 1033 – Crimes by or Affecting Persons Engaged in the Business of Insurance Health care fraud carries up to 10 years, rising to 20 years if someone is seriously injured and up to life imprisonment if the fraud results in a death.6Office of the Law Revision Counsel. 18 U.S. Code 1347 – Health Care Fraud State penalties vary but frequently include both imprisonment and fines that scale with the dollar amount involved.
Civil Recovery
Criminal charges aren’t the only route. Insurers can file civil lawsuits to recover money already paid on fraudulent claims. When fraud involves an organized scheme, such as a staged-accident ring or a network of fraudulent medical clinics, the federal RICO statute allows the injured party to recover three times the actual damages plus attorney’s fees.7Office of the Law Revision Counsel. 18 U.S. Code 1964 – Civil Remedies In federal criminal cases, judges can also issue restitution orders requiring convicted defendants to repay victims. A restitution order acts as a lien against the defendant’s property, remains enforceable for 20 years, and follows the offender through prison and supervised release.8Justice.gov. Restitution Process (Fraud and/or Financial Crimes)
What to Do If Your Claim Is Referred
Finding out your claim has been sent to an SIU is stressful, but referral doesn’t automatically mean the insurer thinks you’re committing fraud. Sometimes claims are flagged by automated systems based on statistical patterns, and the review clears quickly. How you handle the process still matters.
Cooperate, but know the stakes. Your policy almost certainly contains a cooperation clause requiring you to assist with the investigation, provide requested documents, and submit to an EUO if asked. Refusing gives the insurer a contractual basis to deny your claim regardless of its merits. Cooperation doesn’t mean you should volunteer information beyond what’s asked or speculate about facts you’re uncertain of.
Organize your documentation early. Gather receipts, photographs, police reports, medical records, repair estimates, and any communications with the insurer. Having records in order before the investigator asks for them speeds the process and demonstrates good faith. If you no longer have a document, say so honestly rather than guessing at the details.
Consider hiring an attorney. If the investigation escalates to an EUO, or if you sense the insurer is building a case to deny your claim rather than verify it, legal representation becomes important. An attorney experienced in insurance disputes can advise you on what you’re required to provide, accompany you to sworn proceedings, and push back if the insurer crosses into bad faith by unreasonably delaying your claim or demanding information that isn’t relevant.
Watch the clock. Insurers must investigate and resolve claims within a reasonable time under every state’s unfair claims practices laws. Exact deadlines vary, but an investigation that drags on for months without explanation may itself constitute bad faith. If your insurer goes silent or repeatedly requests the same information without progressing toward a decision, document every interaction and consider filing a complaint with your state’s department of insurance.