IX. Theories of Liability & Common Defenses
Plaintiff's Theories of Liability
NegligenceCiv. Code § 1714(a)
The general-duty statute imposes ordinary-care liability for harm caused by "want of ordinary care or skill." Plaintiff must prove: (1) duty; (2) breach; (3) actual and proximate causation; and (4) damages. Rowland v. Christian (1968) 69 Cal.2d 108 provides the multi-factor duty framework courts use when duty is disputed. This is the foundational theory in most California personal injury cases.
Negligence Per SeEvid. Code § 669
Violation of a statute designed to prevent the type of harm suffered, by a member of the protected class, creates a rebuttable presumption of negligence. In motor-vehicle cases, Vehicle Code violations routinely supply the standard of care. The plaintiff need not re-prove the content of the statute — it speaks for itself.
Strict Products LiabilityGreenman v. Yuba Power (1963)
A manufacturer is strictly liable when a product placed on the market proves defective and injures a user — without proof of negligence. Barker v. Lull Engineering (1978) 20 Cal.3d 413 established the two-pronged design-defect test: consumer-expectations and risk-benefit. The risk-benefit prong shifts the burden to the defendant to prove the design's benefits outweigh its risks.
Premises LiabilityRowland v. Christian; Gov. Code § 835
Owners and occupiers owe a duty of reasonable care to persons on their property. Ortega v. Kmart (2001) 26 Cal.4th 1200 holds that constructive notice can be proven by circumstantial evidence, including inadequate inspection intervals. For public-entity property, Government Code § 835 requires proof of dangerous condition, foreseeability, and notice — plus absence of applicable statutory immunity.
Respondeat SuperiorCommon Law; Lab. Code § 3601
An employer is vicariously liable for torts committed by employees within the scope of their employment — even if the employer itself was not negligent. Independent contractors generally fall outside respondeat superior, but misclassification of employees as contractors is frequently litigated, especially in app-based transportation cases.
Wrongful Death / SurvivalCCP §§ 377.60, 377.34
Statutory heirs recover for lost support, services, and society under the wrongful death claim (§ 377.60). The decedent's estate pursues the decedent's own claims via the survival action (§ 377.34). Note: the SB 447 window allowing pre-death pain recovery in survival actions closed January 1, 2026 — legislative extension must be confirmed before relying on it in new filings.
Common Defense Theories
Comparative FaultLi v. Yellow Cab Co. (1975)
California's pure comparative negligence regime reduces — but never eliminates — the plaintiff's recovery by the plaintiff's percentage of fault. Even a 99%-at-fault plaintiff recovers 1% of proven damages. Defendants invest significantly in plaintiff-fault narratives via accident reconstruction, smartphone data downloads, and prior inconsistent statements at deposition.
Howell / Corenbaum Medical Bill CapHowell v. Hamilton Meats (2011)
Past medical damages are capped at the amount actually paid or incurred by the plaintiff's insurer — not higher billed charges. Corenbaum v. Lampkin (2013) extends this to bar use of billed charges as a foundation for future-medical expert opinions and to prevent anchoring non-economic damages to inflated bills. This is routinely the defense's most powerful damages-limiting motion in limine.
Primary Assumption of RiskKnight v. Jewett (1992)
In inherently risky activities — contact sports, extreme recreation, fitness training — co-participants and operators owe no duty to protect against risks inherent to the activity. This is a no-duty rule (not mere comparative fault) and is a complete defense when applicable. Defendants frequently seek to characterize incidents as falling within this doctrine even outside traditional sports contexts.
Government ImmunityGov. Code §§ 830.2, 830.4, 830.6
Public entities enjoy statutory immunities: trivial defect doctrine (§ 830.2); sign/signal immunity (§ 830.4); design immunity for approved plans (§ 830.6); natural-conditions immunity for unimproved property (§ 831.2); and unpaved road immunity (§ 831.4). Each is a factual inquiry — none is automatic — and courts carefully scrutinize whether the conditions for immunity are met.
Product Alteration / MisuseProducts Liability Defense
A defendant may defeat a strict products liability claim by proving the product was substantially altered after leaving the defendant's control, or used in a manner not reasonably foreseeable at manufacture. The defense requires evidence of the specific alteration or misuse and its causal role in the accident — not merely that some misuse occurred.
Causation ChallengesGeneral & Specific Causation
Defense biomechanical experts challenge both general causation (whether the mechanism could cause the claimed injuries at all) and specific causation (whether this plaintiff's injuries were in fact caused by this accident). Independent medical examinations, pre-accident records, and treating-physician credibility attacks are standard defense tools in soft-tissue and low-property-damage claims.
This analysis is for informational purposes only and does not constitute legal advice. Consult qualified counsel for advice specific to your situation. Attorney advertising.
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