The Main Street Journal has a post this morning providing some interesting analysis of the Mary Winkler case. Ms. Winkler is the minister's wife in Selmer, Tennessee who allegedly fired a gunshot into the back of the parson's head recently.
While no one yet knows anything about the motive, the MSJ suggests that her lawyers may be laying the groundwork, at least in the public eye, for an insanity defense. While not much is known about Ms. Winkler's state of mind, overall, insanity defenses have not fared particularly well since John Hinckley used it successfully after shooting President Reagan a quarter of a century ago. Overall, its more restricted acceptance is a good thing.
The foundational rationale of an insanity defense is that the mental state of the defendant is such that he or she no longer understands the difference between right and wrong. Not knowing that difference warrants the judgment that the perpetrator did not knowingly commit a criminal act. However, any time a person seeks to keep secret their actions, by doing so they demonstrate an awareness that what they are doing is wrong. As such, it can be argued that anyone who makes an effort to conceal their actions is not legally insane. Thus, if Ms. Winkler intentionally killed her husband in the bedroom with the gun at a time when she was certain no one would be around, that fact alone would indicate that she was not legally insane.
Criminal defense lawyers don't like such a narrow definition, and by writing this I have probably just guaranteed that I will never be permitted to be on a jury if the attorney in the case wishes to present such a defense.