Spearin Doctrine
The rule that a contractor who follows an owner's plans and specifications is not liable for resulting defects caused by those plans, because the owner impliedly warrants their adequacy.
Named for the 1918 United States Supreme Court decision United States v. Spearin, the doctrine holds that when an owner furnishes design plans and specifications and requires the contractor to follow them, the owner impliedly warrants that the plans are adequate and suitable for their intended purpose. If a contractor builds exactly to those specifications and a defect results from a design flaw rather than the contractor's own workmanship, the contractor is generally shielded from liability and the owner (or its design professional) bears responsibility.
The doctrine is most contested in design-build and design-bid-build disputes where the line between 'design specification' (which the contractor must simply follow) and 'performance specification' (which leaves the contractor discretion to choose a means and method, and therefore more responsibility for the outcome) is blurry. Owners frequently try to contract around Spearin with clauses requiring the contractor to review and certify the adequacy of the plans, and courts vary on how much such clauses shift responsibility back to the contractor.
Juricratic treats Spearin as an allocation dial rather than a binary defense: the simulation lets the user weight how much of a defect's causation traces to design versus workmanship, since real defects often have mixed causes, and shows how the ultimate liability split between owner, designer, and contractor shifts as that allocation moves.
How it actually shows up
Contractors invoke the Spearin doctrine to defend against defect claims that trace back to an owner-furnished design, while owners and their design professionals push back by arguing the specification was performance-based, that the contractor had a duty to flag an obvious design error, or that a review-and-certify clause shifted responsibility to the contractor.
- Does Spearin apply to performance specifications?
- Generally no, or only in limited form; performance specifications describe an end result and leave the contractor discretion over methods, which typically shifts more responsibility for the outcome onto the contractor.
- Can a contract waive the Spearin doctrine?
- Many contracts try to, through clauses requiring the contractor to review and verify plans, but courts differ on whether general review obligations are enough to override the implied design warranty, especially for latent design defects a contractor could not reasonably have caught.
- Who typically bears liability if Spearin applies?
- The owner, and often in turn the owner's architect or engineer under a separate professional negligence or breach-of-contract theory for furnishing defective plans.
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