We develop a 2-country model of legal dynamics in which each country's social welfare depends generally on its actual law, its culturally ideal one, its technologically efficient one and the actual law of the other country. In our model, countries are better off when all these laws coincide....

In common law legal systems, there is no legal duty to rescue persons in danger. By contrast in code-based legal systems, the principle of duty to rescue does apply. What is behind this difference? To answer this question, we develop a new model extending the reach and strength of the standard...