Arson or Accident: How Experts Determine the Cause of a Fire

Understanding the red flags of arson is essential for insurance adjusters, risk managers, and law enforcement. Once you’ve learned to find the first signs of an arson case, you can begin to develop your approach to determine the cause of a fire.

Fire investigators follow a systematic approach known as fire cause and origin analysis. This process helps determine where a fire started and what ignited it. The key steps include:

Fire Cause and Origin Investigation

Investigators analyze burn patterns, fire damage, and potential accelerants to pinpoint the fire’s ignition source. They also assess possible accidental causes—like electrical malfunctions or unattended candles—to rule out non-criminal explanations. In suspected arson cases, cause and origin reports serve as key evidence in court, helping prosecutors establish intent, method, and potential suspects. For insurance adjusters, these findings are crucial in detecting fraud, ensuring fair claim processing, and protecting insurers from paying out on fraudulent losses.

1. Establishing the Point of Origin

Every fire has a starting point, and identifying it is the first step in determining its cause. Experts look for the lowest and most intense burn patterns because fire spreads upward and outward. Clues like V-patterns on walls, melted materials, and heat discoloration help pinpoint where the blaze began.

2. Identifying Burn Patterns

Burn patterns provide critical insights into how a fire moved through a structure. Experts analyze char depth, heat shadows, and smoke residue to reconstruct the fire’s behavior.

• V-patterns suggest a point of origin, where flames fanned out in a triangular shape.
• Pour patterns on the floor may indicate the presence of accelerants like gasoline.
• Unusual burn damage (e.g., isolated burn spots) could hint at multiple ignition points—a classic sign of arson.

3. Examining Fire Accelerants

Arsonists often use accelerants (flammable substances that speed up a fire) to ensure rapid and widespread destruction. Investigators collect debris samples and use gas chromatography-mass spectrometry (GC-MS) to detect traces of gasoline, lighter fluid, or other accelerants. A fire that burns unusually hot and fast often raises red flags.

4. Electrical vs. Accidental Causes

Accidental fires often originate from electrical faults, appliances, or human error (like unattended candles or cooking mishaps). Fire experts carefully examine electrical systems, appliance wiring, and overloaded circuits to rule out non-criminal causes. If no clear accidental source is found, arson becomes a strong possibility.

Kentucky Arson Plot Revealed

In an audacious scheme that culminated in tragedy, Steve and Brandi Pritchard of Columbia, Kentucky, orchestrated an arson to defraud their insurance company. On June 24, 2011, Brandi secured a $50,000 renter’s insurance policy for their home’s contents. Just six days later, in the early hours of June 30, the couple ignited a fire that rapidly consumed their rented residence. Firefighters arrived promptly, battling the intense flames. Amid their efforts, Assistant Chief Charles Sparks, 49, suffered a heart attack and tragically passed away eight days later,
according to the Federal Bureau of Investigation.

The fire’s ferocity obliterated potential forensic evidence, initially hindering arson investigations. Undeterred, the Pritchards filed an insurance claim, inflating the value of their lost possessions to maximize the payout. However, community members reported hearing the couple boast about their involvement, prompting a deeper probe. Years later, the FBI’s renewed investigation uncovered sufficient evidence to prosecute. Steve Pritchard received a 30-year prison sentence, while Brandi was sentenced to over 10 years, highlighting the severe consequences of such fraudulent actions.

Discrepancies in Reported Losses

When investigating a potential arson case, establishing whether a claimant had the opportunity to commit the crime is crucial. While direct access to their home or vehicle is an obvious factor, there are deeper indicators that can raise suspicion. Discrepancies in reported losses and questionable documentation are key signs that an arson-for-profit scheme may be at play.

Loss Discrepancies:

A detailed analysis of a claimant’s loss inventory can reveal inconsistencies that point to fraud. Some red flags in report losses include:

Conflicting Reports: A loss inventory that significantly differs from the police report suggests the claimant may be inflating or fabricating their losses.

Unusual Purchases: If the loss inventory shows an unusually high number of recent purchases, it may indicate premeditation.

Excess Documentation: While some claimants struggle to provide receipts for their belongings, others may go overboard, supplying receipts for every single item—even older, low-value possessions. This over-preparation can be a sign of staging.

Lack of Proof for Expensive Items: Claimants unable to provide receipts, credit card statements, canceled checks, or other proof of ownership for recent high-value purchases may be fabricating the losses.

Memory Lapses: Being unable to recall key details about the purchase of high-priced items—such as the store name, date of purchase, or payment method may suggest dishonesty.

Signs of Fabrication

Here are some warning signs to be on the lookout for when it comes time to analyze receipts from a potential arson investigation:

Incorrect Sales Taxes: Fake receipts often have sales tax amounts that don’t match state or local tax rates.

Lack of Store Branding: Legitimate receipts typically feature a company logo or watermark, while fraudulent receipts may be blank or missing store details.

Sequentially Numbered Invoices: If receipts or invoices from the same supplier are numbered sequentially, it suggests they were printed together rather than accumulated over time.

Reverse Order Invoice: A receipt’s date should align with the order of its invoice number. If a newer purchase has an earlier invoice number, it could indicate tampering.

Credit Card Receipts: A legitimate credit card transaction includes an approval code. The absence or inaccuracy of this code on receipts is a clear red flag.

When determining whether a claimant had the opportunity to commit arson, investigators must look beyond basic access to the property. A detailed review of the claim submission, loss inventory, potential red flags, and motives provides a well-rounded, 360 view of the whole case rather than just the incident.

Don’t miss our other Arson-related articles and make sure to check out our continuing education page to sign up for our next arson webinar!

Check out our sources!

Federal Bureau of Investigation. (2019, May 20). Kentucky couple sentenced for arson and fraud. FBI News. [https://www.fbi.gov/news/stories/kentucky-couple-sentenced-for-arson-and-fraud-052019](https://www.fbi.gov/news/stories/kentucky-couple-sentenced-for-arson-and-fraud-052019)

Potts, B. C. (1980). Arson: Insurance fraud is a prime motive. Fire and Arson Investigator, 30 (4), 47–54. Retrieved from https://www.ojp.gov/ncjrs/virtual-library/abstracts/arson-insurance-fraud-prime-motive