Also known as: substantially · substantial performance · substantial evidence
Written by attorneys · grounded in primary & secondary sources — see below
A significant or material degree, amount, or extent that satisfies a legal threshold for triggering a consequence or standard under a rule.
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Sebastian Santos drove his truck at high speed through a residential area while texting. His vehicle struck and killed a pedestrian. The court found that Santos's conduct deviated substantially from that of a reasonable driver, satisfying the criminal negligence standard and supporting an involuntary manslaughter conviction.
Serena Soto sued her former business partner in federal court over a disputed contract. The partner moved to join a third-party supplier whose absence would expose Soto to a substantial risk of inconsistent obligations in parallel state proceedings. The court ordered joinder under Rule 19.
Stella Shapiro, an economist, based her damages calculation on industry surveys that would ordinarily be inadmissible hearsay. The proponent showed that the probative value of the surveys in helping the jury evaluate her opinion substantially outweighed any prejudicial effect, allowing disclosure to the jury under Rule 703.
Judge Scott Summers issued a press release criticizing a pending criminal defendant's character. Defense counsel moved to disqualify the judge, arguing the statement might substantially interfere with a fair trial. The court granted the motion and reassigned the case.
Samuel Soto left a firm that had represented a client in a contract dispute. The firm later took on a new matter substantially related to that dispute. Because the matters were substantially related, the firm implemented screening procedures under Rule 1.10(b)(1) to avoid imputation of the conflict.
Sabrina Shah, a delivery driver for Sterling Dynamics, deviated slightly from her route to drop off a personal package but remained within the authorized time and space limits of her shift. The court held the detour occurred substantially within those limits, rendering the employer vicariously liable for the resulting accident.
Criminal negligence requires a substantially greater deviation from reasonable conduct than civil negligence. This higher threshold ensures only egregious conduct supports involuntary manslaughter liability when death results.
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A risk qualifies as substantial when the absent party's interest creates a practical likelihood of double or conflicting obligations for an existing party. Courts assess this based on the concrete overlap of claims and remedies.
…1854, c. 49, § 1, set forth in 3 H. Gammel, Laws of Texas 1502 (1898). This was soon modified into language that has remained substantially unchanged to the present time. See Texas Penal Code of 1857, c. 7, Arts. 531-536; G. Paschal, Laws of Texas, Arts. 2192-2197 (1866); Texas Rev. Stat., c. 8, Arts. 536-541 (1879); Texas Rev.…
…Clause, the Framers similarly chose to employ the “life, liberty, or property” formulation, though they otherwise deviated substantially from the States’ use of Magna Carta’s language in the Clause. See Shattuck, The True Meaning of the Term “Liberty” in Those Clauses in the Federal and State Constitutions Which Protect…
…Court in Plessy v. Ferguson , 163 U.S. 537. Under that doctrine, equality of treatment is accorded when the races are provided substantially
…the Fifth Amendment as made applicable to the States by the Fourteenth Amendment. Pp. 123-138. (a) The restrictions imposed are substantially
…with Wuchter v. Pizzutti , 276 U. S. 13, or, where conditions do not reasonably permit such notice, that the form chosen is not substantially
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The balance turns on whether the data meaningfully assists the jury in evaluating the expert's opinion without creating unfair prejudice that exceeds that assistance. Courts weigh the data's reliability in the field against its potential to mislead.
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Interference occurs when the statement creates a reasonable expectation of affecting the outcome or fairness of a pending matter. Nonpublic statements receive the same scrutiny if they pose a substantial risk to trial integrity.
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Matters are substantially related when they involve the same or overlapping facts, transactions, or legal issues such that confidential information from the prior representation would be material to the new matter.
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Conduct falls within those limits when it takes place during the time and in the geographic area the employer has authorized, even if the employee makes minor deviations that do not take the activity outside the overall scope.
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