Google Pit Bull police dog.
They're everywhere and they excel at their jobs, thanks to their high intelligence and trainability.
Want an intelligent dog, get a poodle. Want a reliable, intelligent dog with the ultimate bite force, get a GSD.
The american pit pull has been bred to insanity. It’s practically a predatory breed.
Search Dogsbite.org to read about all the pitt bulls the police shoot or run over with their cars to halt attacks. Note the number of reports that stress the heavy gauge ammo combined with multiple shots required to stop the animal.
http://www.dogsbite.org/blog-posts-police-shootings-of-pit-bulls.php