How to Prove Negligence at Work: Legal Steps in California

Civil Code § 1714 establishes the general duty of ordinary care: every person is responsible for injuries caused to another by a want of ordinary care or skill in the management of their property or person. In a workplace context, that standard runs through the employer’s obligations under both the civil code and California’s labor statutes.

Element 1: Duty of Care

An employer owes employees a legal duty of care sourced from at least two independent authorities. Civil Code § 1714 imposes a general reasonable-person obligation on every person, including employers. Labor Code § 6400(a) adds a statutory layer: every California employer must furnish employment and a place of employment that is safe and healthful for the employees therein, without exception by industry or workforce size.

On multiemployer worksites, § 6400(b) extends accountability to four categories of employer even when their own employees were not the ones exposed to the hazard: the exposing employer (whose workers faced the hazard), the creating employer (who generated the hazard), the controlling employer (responsible by contract or practice for site safety), and the correcting employer (tasked with fixing the hazard). This matters when a general contractor, subcontractor, or staffing agency is involved.

Element 2: Breach of Duty

Breach occurs when the employer’s conduct falls below the reasonable-person standard of Civil Code § 1714 or violates the safe-workplace mandate of Labor Code § 6400(a). Common patterns include: failing to provide required safety equipment, ignoring documented hazards, failing to train employees on known risks, or allowing conditions to persist after prior incidents put the employer on notice. The breach need not be intentional. Carelessness or inaction is enough.

Element 3: Causation (the “Substantial Factor” Standard)

California’s causation standard requires that the defendant’s breach was a substantial factor in bringing about the harm. A substantial factor is more than trivial; it does not need to be the only cause. Where multiple parties contributed, a jury may apportion fault among all of them. That apportionment flows directly from California’s pure comparative negligence rule, established by the California Supreme Court in Li v. Yellow Cab Co. (1975) 13 Cal.3d 804: a worker’s own partial fault reduces (but does not eliminate) recovery in proportion to their percentage of fault. Even a worker found to be predominantly responsible for their own injury may still recover a share of damages from another at-fault party.

Element 4: Damages

The worker must have suffered actual, quantifiable harm. Recoverable categories include medical expenses, lost wages, loss of future earning capacity, pain and suffering, and other economic and non-economic losses. Without demonstrable harm, even a clear breach of duty does not produce a viable negligence claim.

Illustrative scenario: A warehouse worker at a distribution company repeatedly reports to her supervisor that a pallet lift lacks its required safety guard. The supervisor acknowledges the report but takes no corrective action. Six weeks later, the worker’s hand is caught in the mechanism, requiring surgery and two months of lost work. The employer’s knowledge of the hazard plus its failure to correct it supports both a breach of Labor Code § 6400(a) and the reasonably-careful-person standard under Civil Code § 1714. Whether this rises to a civil claim, however, depends on whether an exception to the workers’ compensation exclusivity rule applies. (This is a hypothetical for illustration only, not a description of any client matter.)