With the stroke of his pen in 2005, Jeb Bush, then governor of Florida, ignited enthusiasm for “stand-your-ground” laws. Citizens who “reasonably believed” their lives to be threatened were given the right to “meet force with force, including deadly force”— even in public places and, critically, without the duty to try and retreat first. More than 20 states have passed similar laws since then. Critics warned that, rather than protecting self-defence rights as intended, the bill would result in unnecessary deaths. Research published in the Journal of the American Medical Association appears to vindicate those fears. Soon after the law took effect in Florida, there was a sudden and sustained 24% jump in the monthly homicide rate. The rate of homicides involving firearms increased by 32%. The authors found that in states without a stand-your-ground law over the same time period those rates remained flat, suggesting that a nationwide crime wave was not to blame for the abrupt increase.