Rescue organizations do their best to check the dogs termpermant before putting them up for adoption, they have experts. Especialy with a breed like doberman I would think they do due dilligence. However, many times you just don't know the history of a rescue.
There are a lot of reasons for rescue, only one of which is abuse/neglect. Sometimes dogs just don't get along with the families they live with, sometimes older folks have to get rid of dogs when they go to retirement living situations, sometimes younger people move to apartments and have to get rid of dogs.
Personally I would never get a puppy. Rescues and adoptions are almost always already house-trained. Puppies pee, poop, and puke in the house because they don't know better. Also, puppies need someone home with them 100% of the time. - Keep that in mind. One of my dogs was a purebred Adoption from a family he just didn't work out with and one was a full-on rescue (dropped off at the pound heartworm positive with suspicion of neglect). They are both precious!
I had a friend years ago who had a doberman - what a sweetheart that dog was!!!! Good luck!