Pit Bull Kills 3 Week Old Infant

It seems like this was just a terrible accident.
From the Detroit Free Press: A 3-week-old girl was killed by a pit bull Thursday after her mother left her in a car seat on the floor inside a house on Detroit’s west side, police said.
Sgt. Eren Stephens said the newborn’s mother went to a home about 5:45 p.m. in the 7700 block of Stahelin and took the infant inside with her. The mother put the girl, still strapped into the seat, on the floor, not knowing there was a dog loose in the house.
The mother, Stephens said, stepped away from the infant for a moment, but when she returned the pit bull was mauling the girl. The baby was taken to a hospital, but she died of her injuries.
Police did not release the name of the girl or her 24-year-old mother.
The dog was removed from the home Thursday night and taken to an animal control facility. http://www.freep.com/article/20121004/NEWS01/121004082/detroit-girl-killed-by-pit-bull?odyssey=tab|topnews|text|FRONTPAGE
You really can't blame the dog as it probably thought the baby was toy.  And if the mom truly knew there was no dog int he house, then she should not be at fault.  Finally, if the homeowner didn't know the mom brought the baby, then she can't be held to blame.
But if an adult knew there was a dog running around the house, then they are at fault.  But in any case, it is certainly a tragedy.