When deciding whether to admit evidence, it’s usually easy to answer the question of relevancy. The difficulty in determining admissibility lies in the numerous rules that exclude relevant evidence. One important set of exclusionary rules is based on public policy concerns. For instance, if Pete hits Sally’s car and offers to pay her medical expenses, his offer will not be admissible. This is because, as a matter of public policy, we want to encourage people to do nice things for other...