It's hard to imagine that we live in a country where you can be assaulted by law enforcement for merely walking your dog off leash, as was the case with Gary Hesterburg, who was tasered by a federal ranger while walking his two small dogs off leash in Golden Gate National Park.  Whether the man was belligerent to the officer, the article doesn't say, but unless he attempted to physically attack the ranger, I see no excuse for using what could be lethal force against a man walking his dogs.  People don't always survive being tasered.  This is also a weapon used to bring someone down and should be handled as though it were as lethal as a firearm.  I like to think the ranger wouldn't have gunned down the dog walker for his grand offense of having his dogs off leash, but in the America of 2012, who knows?
At any rate, fellow dog walkers, better keep those dogs leashed at all times or the outcome could be shocking.