Written by attorneys · grounded in primary & secondary sources — see below
A standard or condition that deviates from what reason or a reasonable person would accept under the circumstances. The deviation may render an act, risk, fee, or detention impermissible when it lacks rational basis or imposes excessive burden.
Sources & Authorities
How it applies
Common Examples
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Larceny Deprivation Period
Umar Usmani took a neighbor's bicycle and kept it hidden for six months before returning it. The extended period of deprivation satisfied the intent element because it lasted so long that the loss became unreasonable from the owner's perspective.
Warrantless Home Entry
Federal agents entered Ulf Ulfsson's residence without a warrant after receiving an anonymous tip about contraband. The entry constituted an unreasonable search because no exigent circumstances or other exception justified bypassing the warrant requirement.
Duplicative Discovery Requests
Uptown Apparel already produced transaction summaries in response to initial requests from Ultra Precision. When Ultra Precision demanded the identical records again plus documents it could obtain directly from a government agency, the court limited the requests as unreasonably cumulative and obtainable from a more convenient source.
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Cases
Statutes
Federal Rules
Uniform Acts
Model Codes
Common Law
Excessive Attorney Fee
Umar Underwood agreed to pay his lawyer a flat fee of $75,000 for a routine contract review that required only eight hours of work. The court found the fee unreasonable after weighing the time required, the simplicity of the matter, and the lawyer's customary charges for similar services.
Landlord's Undisclosed Hazard
Uliana Ustinova leased an apartment from Ultimate Solutions without being told that a loose stair railing posed a serious fall risk. The landlord's failure to disclose the condition created an unreasonable risk of physical harm, exposing the company to liability for injuries that occurred after the tenant took possession.
Offensive Contact Without Intent
Uriah Urban bumped into a passerby while rushing through a crowd, creating an unreasonable risk of an offensive touching. Because Uriah lacked the intent to cause harmful or offensive contact, he avoided battery liability even though the same conduct would have been negligent if it threatened bodily harm.
Common questions
Frequently Asked
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How does the reasonableness standard differ between Fourth Amendment searches and discovery limits?+
The Fourth Amendment prohibits unreasonable searches and seizures absent probable cause and a particularized warrant. Discovery rules require courts to limit requests that are unreasonably cumulative or obtainable from more convenient sources. Both standards protect against excessive government or litigant intrusion but apply distinct triggers and remedies.
Supporting sources
When does an attorney's fee become unreasonable under professional conduct rules?+
A fee is unreasonable when it exceeds what is appropriate after considering time and labor required, novelty of the questions, skill needed, likelihood of precluding other work, customary local charges, and results obtained. Courts examine these factors to prevent overreaching.
Supporting sources
What makes a risk of harm unreasonable in landlord-tenant or tort contexts?+
A risk is unreasonable when a reasonable person would recognize the danger and take precautions, yet the responsible party fails to disclose or mitigate it. Liability follows if the tenant or victim lacks knowledge of the condition and the landlord or actor knows or should know of the risk.
Supporting sources
Does an honest but unreasonable belief in self-defense reduce murder to manslaughter?+
In some jurisdictions an honest but unreasonable belief that deadly force is necessary mitigates murder to voluntary manslaughter. The belief must be genuine though objectively unreasonable under the circumstances.
Supporting sources
410 U.S. 113 (1973)Constitutional Law
…terms of the taking of property; the freedom of speech, press, and religion; the right to keep and bear arms; the freedom from unreasonable searches and seizures; and so on. It is a rational continuum which, broadly speaking, includes a freedom from all substantial arbitrary impositions and purposeless restraints . . . and…