Also known as: reasonable scientific certainty · to a reasonable degree of scientific certainty · reasonable certainty · scientific certainty
Written by attorneys · grounded in primary & secondary sources — see below
A standard requiring that facts, identifications, terms, or losses be established with enough precision to support reliable legal conclusions or enforcement.
Rachel Ramirez emailed Redwood Bank a signed note offering to lease Suite 500 starting in the fall at the posted rate. The note identified the suite but supplied no rent figure or lease duration. Redwood later leased the space to another tenant. Rachel sued for breach, but the court held the writing failed to state essential terms with reasonable certainty, so the statute of frauds barred enforcement.
Renee Rogers executed a will that referred to an existing notebook listing specific personal property items and named devisees. The will expressed clear intent to incorporate the notebook and identified it by date and location. After death the notebook was offered for probate. The court admitted it because the notebook was identified with reasonable certainty at the time of execution.
Select any source to read its text and confirm it supports the definition.
Roberto Reyes was the target of a complaint, but officers lacked his full name. The warrant described him as the male driver of a red pickup with a specific license plate seen at the robbery scene. Police executed the warrant and arrested the correct individual. The court upheld the warrant because the description identified the defendant with reasonable certainty.
Rebecca Ross bought a used car from Redline Automotive after the dealer misrepresented its accident history. She proved the purchase price exceeded the car's actual value and sought benefit-of-the-bargain damages. The court awarded the difference in value but denied additional lost-profit claims because those amounts were not proved with reasonable certainty.
Raymond Ramos spent $80,000 preparing a site for a contract with Regal Apparel that the company later breached. He sought recovery of those expenditures as reliance damages. Regal proved Ramos would have lost $25,000 even if the contract had been performed. The court reduced the award by that amount because the projected loss was shown with reasonable certainty.
Renata Russo claimed $300,000 in lost profits after a supplier breached a distribution contract. Her projections rested on untested expansion into three new states with no prior sales data. The court denied the claim because the evidence did not establish the amount of loss with reasonable certainty.
The standard requires enough precision in the evidence to permit a reliable legal conclusion without speculation. Courts accept reasonable estimates supported by data but reject purely conjectural projections.
No. The same phrase appears in contract, tort, property, and criminal-procedure rules that demand sufficiently certain identification of terms, losses, or persons.
A writing satisfies the statute only when it states essential unperformed terms with reasonable certainty so a court can determine the parties' obligations.
Yes, when the claimant supplies historical performance data or reliable market benchmarks that allow a reasoned calculation rather than mere speculation.
…mitigates the degree of criminality or punishment, we think the State may assure itself that the fact has been established with reasonable certainty. To recognize at all a mitigating circumstance does not require the State to prove its nonexistence in each case in which the fact is put in issue, if in its judgment this would be too…