So two of her dogs have displayed agressive behavior? Sounds like bad ownership to me. Blame the owner not the dogs, regardless of who the owner is.

Am I correct that in England Bull Terriers are the same breed that they are in the U.S.? The same dog as Spuds McKenzie? Or are these Pit Bull Terriers that Princess Anne owns?

I've never heard of agressive Bull Terriers or Miniature Bull Terriers and have known quite a few.