The article focuses on Ratio Communis, which accounts for a quality component of a rule that renders an efficient law, and it also discusses its impact on mixed jurisdictions in context to civil liability. If certain issues are common to distinct legal systems and are able to resolve fixes in an efficient manner then it is of no significance to manifest which legal system a resolution originated from. The author tries to identify as many Ratio Communis as possible in the field of civil liability and the law of damages in Quebec by a functional comparative approach, in order to verify that mixed legal systems are particularly successful in comparing and weighing of legal solutions of different origins.
Meanwhile, both the fundamental elements of liability and damages (proximity, fault, culpability, force majeure, contributory negligence, non-pecuniary damages and the cap, punitive damages, pure economic loss, relational losses) but also some more specific questions (occupiers’ liability, defamation, liability of managing directors, extra-contractual liability of auditors towards third parties, prenatal injuries) are evaluated in light of the mutual influences of common law and civil law. The results are finally compared with the solutions of European law approximation processes like PETL or DCFR.