The first 2 big rules of gunfighting....
The more well known & highly trained tactics instructors across the US(and on the world wide web) often say; 1) Have a gun! & 2) Use enough gun!
It would be difficult to sit in open court having to explain to a judge & jury(who may know little or nothing about firearms) why you shot a subject 10 or 15 times with a .22LR. A member of a grand jury may say; "couldn't you have used a .38spl or 9mm?
When most people think of .22LR handguns they think of mafia goons or Mossad hitmen.