Also known as: substantially impair · substantially impaired · substantial impairment · materially impairs
Written by attorneys · grounded in primary & secondary sources — see below
A material degree of diminishment in value, utility, or ability that justifies particular legal consequences such as total breach, revocation of acceptance, or constitutional scrutiny of legislation.
Spectrum Financial sues a bank over a shared investment product. A separate judgment for one investor would decide the rights of hundreds of other investors who hold identical interests. The court therefore certifies a class under the rule that protects against adjudications that would substantially impair absent members' ability to protect their interests.
Samantha Stone, a solo practitioner, suffers a stroke that leaves her unable to review client files or appear in court. The impairment prevents her from meeting filing deadlines or advising clients on pending matters. Under the rule, she must withdraw because her condition substantially impairs her ability to represent the client.
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Sophia Singh contracts to buy 500 custom jackets for her boutique. The delivered jackets have inferior linings that tear after one wearing. The defect substantially impairs the value of the remaining jackets to her as a retailer, allowing revocation of acceptance and a claim for total breach.
Stella Shapiro leases a storefront to a tenant who must personally staff the shop each day. The tenant attempts to assign the lease to a corporation that cannot supply the required daily presence. The assignment would substantially impair the landlord's chance of obtaining the promised personal services, so the lease prohibits the transfer.
Sylvia Santos converts a rare sculpture from Santiago Sanchez. She later offers to return the piece promptly after discovering her good-faith mistake. Because the sculpture's value to the owner is not substantially impaired by the brief possession, the court may reduce the damages award.
During a statewide economic crisis, the legislature enacts a temporary moratorium on mortgage foreclosures. The law substantially impairs existing mortgage contracts yet serves an important public purpose of preventing mass evictions. The court upholds the statute under the Contracts Clause because the impairment is reasonable and narrowly tailored to the emergency.
Revocation is permitted only when the nonconformity substantially impairs the value of the goods to the buyer. The buyer must also show acceptance occurred on a reasonable assumption of cure that failed or without discovery of the defect due to difficulty or seller assurances, and revocation must occur within a reasonable time before substantial change not caused by the defect itself.
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For a single shipment the perfect tender rule governs and any nonconformity permits rejection regardless of impairment. Substantial impairment becomes relevant for revocation of acceptance after the buyer has already accepted or for repudiation of future performance under an installment contract.
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A law that substantially impairs existing contractual obligations is subject to Contracts Clause scrutiny. It may be upheld only if it serves an important and legitimate public purpose and is a reasonable and narrowly tailored response to an emergency or other significant problem.
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The lawyer's physical or mental condition must materially impair the ability to represent the client. Once that threshold is met the lawyer must withdraw unless the client consents to continued representation under limited circumstances.
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…seller (or, for that matter, as a result of possession by poltergeists). Where a condition which has been created by the seller materially impairs the value of the contract and is peculiarly within the knowledge of the seller or unlikely to be discovered by a prudent purchaser exercising due care with respect to the subject…