Plaintiff Trimarco, a tenant in defendant Klein's New York City apartment building, was injured when a sliding glass bathtub enclosure shattered as he was stepping from the tub. The panel contained ordinary, non-safety plate glass that fragmented into sharp shards, causing serious lacerations. At trial, Trimarco introduced testimony and documentary proof that, beginning in the 1950s, building owners, contractors, and suppliers widely adopted a practice of using shatterproof or safety glazing (such as tempered or laminated glass, wired glass, or plastic) for bathtub and shower enclosures, especially when replacing older glass. He also offered evidence of later-enacted statutes and codes requiring safety glazing in hazardous locations like tub enclosures for new installations and replacements, not as retroactive mandates but as corroboration of an existing, well-established custom recognizing the hazard of ordinary glass. The landlord did not show that the glass had ever been replaced with safety materials, and there was no claim that any statutory requirement compelled retrofitting of the decades-old panel. A jury returned a verdict for Trimarco. The Appellate Division reversed and dismissed the complaint, concluding, in substance, that the proof was insufficient on negligence and notice. Trimarco appealed to the Court of Appeals.
Whether proof of a well-defined and widely accepted custom to use safety glazing in bathtub enclosures, together with evidence that the landlord failed to follow that custom, is admissible and sufficient to support a finding that the landlord breached the duty of reasonable care and had constructive notice of the hazard posed by ordinary plate glass.
In negligence actions, evidence of industry custom and usage is admissible as probative of reasonable care. When a customary practice is well established and general in the relevant community, a jury may infer negligence from a defendant's deviation from that practice, provided the jury also finds the custom itself to be reasonable under the circumstances. Compliance with custom does not automatically establish due care, and noncompliance is not conclusive of negligence. In premises liability, a landlord may be liable for a dangerous condition on the premises if the landlord created it or had actual or constructive notice of it; widespread custom, and the recognition it reflects of a known hazard and feasible safety measures, can support constructive notice. Statutes or codes adopted after an installation are not retroactive mandates but may be considered as some evidence bearing on the existence and reasonableness of the practice and the recognition of the hazard.
The Court of Appeals reversed the Appellate Division and held that the plaintiff's evidence of a long-standing, general custom to use safety glazing in bathtub enclosures, and the landlord's failure to adhere to that practice, was properly admitted and sufficient to create a jury question on negligence and constructive notice. The dismissal of the complaint was error.
The court explained that custom and usage can illuminate what prudent actors ordinarily do in similar circumstances and thus inform the standard of reasonable care. Where a practice is widespread, well defined, and geared toward eliminating a known danger, a factfinder may treat the practice as evidence of the conduct of reasonably prudent persons. Here, plaintiff presented substantial evidence that, since at least the 1950s, the building industry recognized the danger of ordinary plate glass in bathtub enclosures and customarily used safety glazing when installing or replacing such glass. The landlord offered no persuasive evidence that the glass had been replaced with safety materials or that the custom was not general or reasonable. Although later-enacted glazing statutes and codes could not retroactively impose a duty to replace existing glass, the court permitted them as corroborative of the existence and reasonableness of the custom and the widespread recognition of the hazard; the court emphasized they were not to be treated as creating negligence per se. On the notice element, the court observed that when a hazard has been widely recognized and commonly addressed through a prevailing safety practice, a jury may infer constructive notice: a reasonably prudent landlord is expected to keep abreast of customary safety measures in the field and to implement them when feasible. Because the evidence supported findings that an accepted safety practice existed, that the landlord deviated from it, and that the deviation concerned a known hazard, the case properly belonged with the jury. The intermediate court's dismissal therefore could not stand.
Trimarco clarifies that custom and usage are potent, but not definitive, tools in negligence litigation. It teaches students how to marshal custom evidence to define reasonable care, to argue constructive notice in premises cases, and to situate later-enacted statutes as corroborative rather than retroactive mandates. The case also balances deference to industry practice with the central torts principle that the jury ultimately decides what reasonable care requires.
Trimarco v. Klein stands as a staple of torts pedagogy because it distills the nuanced role of custom in negligence law. It authorizes litigants to use prevailing practices as a lens on reasonable care while preserving the jury's central function to decide whether the practice is reasonable and whether deviation is blameworthy.