It would stop the persecution of innocent dogs merely because they are of the wrong breed and will make the owners of any dog responsible for the actions of their dogs if they cause harm to someone.
Repeal the Dangerous Dogs act and the "banned" status of some breeds. All dogs can bite. Repeal this useless legislation and introduce proper legislation to make the dog owners responsible for the actions of their dogs. NB: the proposals for tagging/chipping of dogs won't work, as, in the main, law abiding people with dogs, who don't cause a problem, will get their dogs chipped, but those that cause a problem won't so it will not do any good whatsoever.