These dogs were bred to work the grounds of aristocracy in Britain, looking to stop, without killing, someone who should not be present. They were bred from bulldogs, who had the speed and athleticism, and mastiffs, who had the power and size needed. Police forces will not work with these animals because they are too powerful to control.
Given a home with firm boundaries, this is a gentle giant. Great with children, it will protect the family to the very best of it’s ability. They can be territorial and should not be moved from family to family.