We were in a similar situation. I live in TX and when our dog bit, the ER didn't really care how it happened, they just wanted to make sure he had his shots.
We got a basset hound from the pound while I was pg with our dd. He was an older puppy, about 6 months old. I have grown up with several bassets and really wanted another one and saw him advertised in the paper for the pound.
Anyway, he was a really sweet dog to us, very loyal, never bit etc, but when I brought dd home from the hospital, he was pissed, literally he looked at me and peed on the floor when he saw her. But he never bothered her until she could walk.
One day she was about 14-15 months old, she was walking across the room to me, and the dog was about 20 feet away from her. Completely unprovoked, I saw him literally fly across the room at her, and aim for her face, growling and barking. He scratched up her cheek, and we rushed her to the ER, I was afraid he damaged her eye. Thankfully, it was just her cheek. He was thrown outside for the night, and the next day went to my parents' home until we placed him in a training program. We put him in a two week intensive program, he lived there for 2 weeks of training. Then we came and took several lessons with him and he came home.
She had never abused him, hurt him, pulled on him or anything. We had taught her from the very beginning how to be nice to him. When we first got him, he was emaciated, and I think he had wild streak in him from living out on his own (my husband had seen him wondering a field before we found him at the pound).
After the training, he was a well behaved dog and left her alone. We thought it was a one time incident and really loved him and wanted to keep him and thought training had fixed the problem. I was wrong! About 3-4 months later, the same thing happened. It was the scariest moment in my life, I couldn't get to her fast enough and pull that dog off of her. Thankfully, she had another scratched cheek, and nothing else. At that point, my parents came over and picked him up that night, and he stayed with them until we found him a home that with an older couple that have no grandchildren. He is now a happy dog, who likes to herd cattle.
Anyway, what we learned later was that training will usually not help an aggressive dog. And they should probably be put down. I just didn't have the heart back then to do it to him, I should have and feel guilty for not putting him down.
We now have a wonderful female black labrador. We got her as a puppy when dd was not quite 2 yrs old. Dd is now almost 4 and they are the best of friends.
But I would definitely be calling CPS on that woman. For the dog to have attacked that many times and she still has it in the home is very frightening. I feel guilty for not getting rid of the dog the first time instead of sending him to training.