Product Design Defect Claims — Proving the Entire Product Line Was Unsafe

## What Makes a Product Design Legally Defective

A design defect claim argues that the engineer's original blueprint — the fundamental specifications from which every unit is manufactured — created an unreasonably dangerous product. Unlike a manufacturing defect, which affects only improperly assembled units, a design defect infects every product ever produced to that design. This breadth of potential liability is why design defect litigation is often pursued as mass torts or class actions, and why manufacturers fight these cases so aggressively.

Two competing legal standards determine whether a design is defective: the consumer expectation test (would an ordinary consumer expect this danger?) and the risk-utility test (do the product's benefits outweigh the risks of its design? Was a safer alternative available?)

The Consumer Expectation Test

The consumer expectation test asks a simple question: did the product perform as safely as an ordinary consumer would have expected when using it in a reasonably foreseeable manner? This test is most easily applied to everyday consumer products where safety expectations are intuitive — a car tire that blows out under normal highway driving conditions, or a children's toy that breaks apart into sharp pieces under normal play.

The test's limitation is that it cannot assess technically complex products where consumer expectations are not informed by technical understanding.

The Risk-Utility Test

The risk-utility test, used in most states either as a replacement for or supplement to the consumer expectation test, weighs the product's benefits against the risks of its specific design. Critically, this test requires the plaintiff to prove that a reasonable alternative design existed at the time of the product's manufacture — a design that would have reduced or eliminated the risk without substantially impairing the product's utility or making it economically infeasible to produce.

An alternative design does not need to be perfect, only safer than the challenged design
The alternative can have existed in competing products, academic research, or the manufacturer's own internal development documents
Demonstrating that the manufacturer considered and rejected safer designs — particularly for cost reasons — is powerful evidence for punitive damages

Building Your Design Defect Claim

Your attorney will retain a design engineer or safety expert who can testify specifically about:

What the product's intended design was and how it functioned in normal use
What specific aspect of the design created the unreasonable risk that injured you
What a safer alternative design would have looked like and how it would have prevented your injury
Whether the alternative was technologically and economically feasible at the time of manufacture

The stronger the evidence that a safer design existed, was known to the manufacturer, and was rejected in favor of lower production costs, the stronger both your liability case and your punitive damages argument become.