Culpa Levissima and the Eclipse of Strict Liability

In Roman law, as interpreted by the medieval jurists, in a gratuitous loan (commodatum), the borrower was liable for culpa levissima, failure to use be as diligent as “most diligent” (diligentissimus). It would seem, then, that a person could be liable for conduct that he could not help. That consequence troubled the medieval canonists a person would then be liable who had not sinned. It troubled the late scholastics because a person would then be liable for an accident, which was not a violation of commutative justice. Some concluded that liability for culpa levissima was a creature of positive law, based on pragmatic considerations but with no grounding in principle. There was another explanation glimpsed by the late scholastics and by Hugo Grotius: commutative justice requires that one who borrows gratuitously indemnify the lender against any loss. Unfortunately, in the following centuries, that explanation was lost from sight.