Nor is there a lack of self-professed “experts” willing to render truly bad advice. Odds are you have heard this one: “If you shoot ‘em outside, drag ‘em inside before you call the cops.” (I’ve even heard a cop say that.) In the era of modern forensics, this advice will doom you to explaining why a trail of DNA (not to mention a host of other forensic evidence) says you are lying.

Sincere study is called for in such serious matters ...