Glossary

Special investigations unit (SIU)

The team inside an insurance company that investigates suspected fraud in claims and applications and refers cases to authorities.

Also called: SIU, fraud unit, special investigations department

A special investigations unit is an insurer's internal fraud team. When a claim or application shows warning signs, the claims adjuster handling it can refer it to the SIU, whose investigators often have law enforcement or long claims experience.

Red flags that can prompt a referral include a policy bought days before a loss, conflicting accounts from drivers and witnesses, damage that does not match the reported crash, treatment patterns repeated across unrelated claimants, and links to known staged accident rings. SIU investigators may take recorded statements, request an examination under oath, inspect vehicles, check databases and public social media, and work with the National Insurance Crime Bureau and law enforcement. Many states require insurers to maintain an anti-fraud plan or unit and to report suspected fraud to the state's fraud bureau.

A referral is not an accusation; many referred claims are paid. But it usually slows the claim, and your policy requires you to cooperate with reasonable requests for documents and statements. Example: a theft claim filed a week after the policy began may be reviewed by the SIU before payment, adding several weeks (hypothetical). If an investigation drags on, ask the insurer in writing what it needs and when it will decide, and contact your state insurance department if deadlines pass. See how insurers investigate fraud.

Last reviewed October 4, 2026

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Related terms

Insurance fraud Deceiving an insurer, or a policyholder, for financial gain, from staged crashes and padded claims to fake policies and lies on applications. National Insurance Crime Bureau (NICB) A nonprofit funded by member insurers that investigates insurance fraud and vehicle theft, works with police and runs the free VINCheck lookup. Hard fraud Deliberately staging or inventing a loss, such as a fake crash, arson or false theft report, in order to collect insurance money. Soft fraud Opportunistic insurance fraud by otherwise honest people, such as padding a real claim or giving false details to lower a premium. Staged accident A crash deliberately caused or faked to file fraudulent insurance claims, often by organized rings of drivers, passengers and complicit providers. Claims adjuster The insurance company employee or contractor who investigates a claim, decides what the policy covers and sets how much is paid.

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