The following is a true, first hand experience and is now on going so I am not passing on a heard story.
My brother and sister in law bought 2 stafordshire terriers (pitt bulls) 15 years ago. ! was killed within the first 2 years they had her when she left the yard and was hit by a car. The other (lucy) was a house pet, loving, gentle but protective of my sister in law and their home. Lucy was a large strong dog but would climb up in your lap and lay until you petted her and would go to sleep unless you made her get down. I never had a moment of fear around her and loved to play with her but my niece (their daughter) would not allow her son to visit their home with the dog inside. My brother was always conscious of her reputation and kept her indoors or in a fenced in yard and she was not allowed to roam free.
Last month my brother was working in their yard moving from the front yard to the fenced back yard. The gate was open and Lucy was in the house. My sister in law came home and automatically let Lucy out without checking the gate. Lucy immediately ran to the front yard. My brother heard a horrific scream and found Lucy attacking a lady who was walking in the street in front of their home.
They've had visits from every conceivable monitoring group from law enforcement to home services. They have been to court and been fined for having a vicious dog (fined $3000.00 and ordered to pay all doctors bills which are now about $10,000) and have been sued. Their home owners insurance is waiving about paying due to the event taking place in the road and not in their yard. My brother and sister in law face losing their home.
Lucy was not ordered to be put down, but my brother has re homed her and she is now relegated to a cage. My brother is absolutely heart broken and we all now have a new apprehension of this breed.