Quoted: “When you’re being unlawfully interfered with by another person, you have a right under the law to defend yourself against that unlawful interference,” says Cecelia Klingele, associate professor of law at University of Wisconsin Law School. “But we also require that when you do so, you’re using force reasonably. So you’re making a reasonable judgement about whether or not you’re in danger, how much danger you’re in, and how much force you need to use in order to protect yourself.”