Regarding the thread’s title of “Idiots with shotguns” it should more accurately read, “Killers with shotguns” since someone is actually attempting murder when shooting at a human, regardless of what he/she is riding in. Whether intentional or not is for the court to decide. Or perhaps this shoe would fit better:”Law needed for idiots who fly downrange of gun ranges.” IMHO
Regarding shot sizes; An increasing number of professional bodyguards and private citizens with concealed carry permits are seeing the benefits of having the first pistol round being of a bird or rat shot type. It is aimed into the face of the perp causing an immediate and instinctive "hands to the face" reaction, especially with eye hit(s). With so many criminals wearing body armor these days and the birdshot not traveling too far past the perp causing collateral damage, the increased use of “bird/rat shot” is a smart move for up close, defensive shooting. The follow-up rounds are usually semi-jacketed hollow-points. Related, I understand the Philippine military did studies on this during WW2 on live Jap prisoners but eventually went to solids in their 45s since most of their shooting would be offensive. I personally carry two Glaser Safety slugs in my .357 S&W and ALWAYS practice face shots these days with the remaining 3 rounds being hollow points especially since I’m strictly carrying for defensive reasons.