My cousin was a police leutenant in charge of training one time.  He said if someone gets shot with a 357, 40 S&W, 45 acp, or such, it will at least knock the breath out of you and probably knock you down.  I also think he was spraying.  When all is said and done, I would like to know what weapon did the most damage.  I would believe the shotgun would have.  If it was, then the gun control people can't say it was because of high capacity magazines or an "assault weapon".  
 
Like I said on another post, in the SEC football games, they have security, checking for alcohol and weapons upon entering a game.  Then if you leave, you can't get back in period.  The same should be done for any place with large crowds.  A little more security, all the theater had to do was hire about 2 more boys to stand by the exit doors and not let anyone leave through them or come in through them during a movie.