The term "less lethal" applies to rounds such as rubber buck shot, rubber batons, sand bag/bean bag rounds, etc. These are generally used in riot control, and are made so that death is not likely to result from being hit with it. It has nothing to do with reduced powed SD loads or any kind of bird shot. http://www.ammoman.com
has some less than lethal 12ga rounds for sale, you can check them out. Rather expensive.