Product Failure Analysis: When Consumer Devices Become Courtroom Evidence

In today’s world, consumer devices—from household appliances to industrial machinery—play a crucial role in daily life. When these products fail, the consequences can be severe, ranging from property damage to serious injury or even fatalities. Determining why a product failed is a complex, technical task that often requires forensic engineering expertise to uncover root causes and establish liability.

At Garrett Forensics, we specialize in investigating product failures, combining engineering knowledge with methodical analysis to provide reliable, defensible evidence that supports legal and insurance cases.

 

Understanding Product Failure

Product failure can occur for many reasons, and understanding the type of failure is the first step in any investigation. Common causes include:

 

1. Design Defects

A product may fail because its design did not account for realistic use, environmental conditions, or safety factors. Examples include appliances that overheat under normal operating conditions, machinery with inadequate guards, or electronics that cannot handle expected voltage variations.

 

2. Manufacturing Defects

Even a well-designed product can fail if it is improperly manufactured. This can include poor assembly, substandard components, improper soldering, or inconsistent material quality. Manufacturing defects are often subtle and require expert inspection to uncover.

 

3. Material Failures

Components may degrade or break due to fatigue, corrosion, or exposure to heat, moisture, or chemicals. For example, wires may overheat due to insulation breakdown, or mechanical parts may fracture under repeated stress.

 

4. Electrical Failures

Electronic products are prone to short circuits, arcing, overloaded circuits, or thermal runaway. Electrical engineers examine circuit boards, wiring, fuses, and insulation to determine if the device malfunctioned internally or if an external factor caused the failure.

 

5. User Error or Misuse

Sometimes, product failures result from misuse or improper maintenance. Forensic analysis helps determine whether the failure was reasonably foreseeable or preventable by design improvements.

 

The Investigative Process

Investigating product failures is a structured, step-by-step process. Each phase combines careful observation, scientific testing, and expert knowledge.

 

1. Scene and Context Examination

Investigators start at the site of the incident. They document environmental conditions, collect damaged products, note burn patterns, component displacement, and surrounding hazards. This stage establishes context for further analysis and may reveal whether the failure was sudden or progressive.

 

2. Product Disassembly and Component Analysis

The device is carefully disassembled, and individual components are examined for signs of failure. Electrical engineers test wiring, circuit boards, switches, and fuses. Mechanical engineers or materials specialists examine gears, housings, and fasteners for wear, cracks, or deformation. Advanced techniques such as microscopy, thermal imaging, and metallurgical analysis may be used to detect hidden flaws.

 

3. Functional Testing

Engineers may replicate operating conditions to see how the device behaves under normal and extreme use. For example, appliances may be powered and monitored for overheating, motors tested for abnormal torque, and sensors evaluated for proper response. Functional testing helps confirm whether the failure can occur as claimed.

 

4. Standards Compliance Review

Devices are evaluated against industry and safety standards such as UL, ANSI, ISO, or NFPA. This step determines whether the product met required safety criteria and whether the failure resulted from design, manufacturing, or operational issues.

 

5. Root Cause Analysis

Using all gathered data, engineers identify the underlying cause of the failure. This may involve combining electrical, mechanical, and materials findings to pinpoint whether the problem originated in design, manufacturing, user error, or external factors.

 

6. Documentation and Expert Reporting

All findings are compiled into detailed, clear reports suitable for legal proceedings. Reports include photographs, diagrams, test results, and step-by-step explanations. In litigation, expert testimony translates complex technical findings into understandable evidence for judges and juries.

 

Real-World Example

A residential kitchen fire was traced to a countertop toaster oven. The fire investigator identified the fire’s origin inside the oven but could not determine if the failure was due to misuse or a design flaw.

Garrett Forensics’ engineers disassembled the device and discovered that the thermostat wiring insulation was too thin and degraded under normal operating conditions. Electrical testing confirmed that the wiring shorted, igniting surrounding materials. This clear combination of fire investigation and forensic engineering analysis provided defensible evidence that the failure resulted from a design defect, not user error.

 

Why Forensic Engineering Matters

Product failures often carry serious financial, legal, and safety consequences. Forensic engineering provides:

Accurate determination of liability for manufacturers, contractors, or users

Scientific insight into design, manufacturing, or usage improvements

Credible evidence for courts, insurers, and regulatory bodies

 

At Garrett Forensics, our multidisciplinary approach ensures every product failure is thoroughly investigated, analyzed, and communicated with clarity. From household appliances to industrial equipment, we provide answers that help prevent future incidents and support high-stakes legal cases.