The question of whether lethal force is more likely, such as occurred in the shooting of Trayvon Martin, when there is a ‘stand your ground’ doctrine like Florida’s, is looked at in a WSJ report.
The ‘stand your ground’ laws create greater flexibility so far as the use of lethal force is concerned, as they remove a person’s ability or duty to retreat when outside the home and they add a presumption of self defence for those who are seen as having a reasonable fear of harm or of death.
They also provide immunity for those who kill someone from civil lawsuits.
For whatever reason, justifiable homicides almost doubled in the decade until 20120 and there has been a sharp increase in those incidents of justifiable homicide that occurred since 2005 when Florida along with 16 other states passed the laws.
While the overall homicide rates in those states stayed relatively flat, the average number of justifiable cases per year increased by more than 50% in the decade’s latter half.
In a new study, an economics professor and a PhD student at Texas A&M University take a broader look at the laws’ effect. The authors, Professor Mark Hoekstra and Cheng Cheng, use state-level crime data from 2000 to 2009 to determine whether the laws deter crime.
The answer, they conclude, is no. In fact, the evidence suggests the laws have led to an increase in homicides.
From the study:
Results indicate that the prospect of facing additional self-defense does not deter crime. Specifically, we find no evidence of deterrence effects on burglary, robbery, or aggravated assault. Moreover, our estimates are sufficiently precise as to rule out meaningful deterrence effects.
In contrast, we find significant evidence that the laws increase homicides. Suggestive but inconclusive evidence indicates that castle doctrine laws increase the narrowly defined category of justifiable homicides by private citizens by 17 to 50 percent, which translates into as many as 50 additional justifiable homicides per year nationally due to castle doctrine. More significantly, we find the laws increase murder and manslaughter by a statistically significant 7 to 9 percent, which translates into an additional 500 to 700 homicides per year nationally across the states that adopted castle doctrine.
Thus, by lowering the expected costs associated with using lethal force, castle doctrine laws induce more of it. This increase in homicides could be due either to the increased use of lethal force in self-defense situations, or to the escalation of violence in otherwise non-lethal conflicts. We suspect that self-defense situations are unlikely to explain all of the increase, as we also find that murder alone is increased by a statistically significant 6 to 11 percent.
It is clear that the homicide rate increases could be driven by people wishing to protect themselves, but they could also occur because of the new doctrine which may not have ended in serious injury for anyone.