Haw. Rev. Stat. § 407
When, after an event, measures are taken which, if taken previously, would have made the event less likely to occur, evidence of the subsequent measures is not admissible to prove negligence or culpable conduct in connection with the event. This rule does not require the exclusion of evidence of subsequent measures when offered for another purpose, such as proving dangerous defect in products liability cases, ownership, control, or feasibility of precautionary measures, if controverted, or impeachment.
HRS § 407
RULE 407 COMMENTARY
This rule is similar to Fed. R. Evid. 407, the Advisory Committee's Note to which points out: "The rule incorporates conventional doctrine which excludes evidence of subsequent remedial measures as proof of an admission of fault.... The...ground for exclusion rests on a social policy of encouraging people to take, or at least not discouraging them from taking, steps in furtherance of added safety. The courts have applied this principle to exclude evidence of subsequent repairs, installation of safety devices, changes in company rules, and discharge of employees, and the language of the present rule is broad enough to encompass all of them."
This rule is limited strictly to exclusion of such evidence when offered as proof of negligence or culpable conduct. The second sentence of the rule lists some of the other purposes for which this evidence may be admitted. The rule varies from Fed. R. Evid. 407 in the addition of "dangerous defect in products liability cases" as one permissible purpose for which remedial measures may be admitted. This codifies the result in Ault v. International Harvester Co., 117 Cal. Rptr. 812, 815-16, 528 P.2d 1148, 1151-52 (1975), where the court held that the rule barring evidence of subsequent repairs should not apply in a products liability case. The Ault court reasoned as follows:
While [the traditional rule] may fulfill this anti-deterrent function [of encouraging, or at least not discouraging, the making of repairs by defendants] in the typical negligence action, the provision plays no comparable role in the products liability field....
The contemporary corporate mass producer of goods, the normal products liability defendant, manufactures tens of thousands of units of goods; it is manifestly unrealistic to suggest that such a producer will forego making improvements in its product, and risk innumerable additional lawsuits and the attendant adverse effect upon its public image simply because evidence of adoption of such improvement may be admitted in an action founded on strict liability for recovery on an injury that preceded the improvement.... In short, the purpose of [the traditional rule] is not applicable to a strict liability case and hence its exclusionary rule should not be gratuitously extended to that field.
In Hawaii, under Stewart v. Budget Rent-a-Car Corp., 52 H. 71, 75, 470 P.2d 240, 243 (1970), a manufacturer, seller, or lessor is strictly liable in products liability cases provided there is proof of "a defective product which is dangerous to the user or consumer or to his property." Evidence of subsequent remedial measures is admissible under this rule to prove such a defect.
Measures that are taken after an event but that are predetermined before the event are not "remedial" under this rule, because they are not intended to address the event; thus, because such measures are not "remedial", evidence of such measures are not inadmissible under the plain language of this rule.115 Haw. 462,168 P.3d 592.