Burns said the dogs, which average 75-80 pounds, look “like a boxer on stilts” and have a face similar to a boxer - with a strong jaw and muscular body. She said none of the dogs looked like they had been used to fight, and there was no indication that dogs were involved in fights on Cockrell’s property.<
They may not have been used to fight, but they formed a pack. Years ago, a friend of mine’s 4 boxers began jumping on a young man they did not know (he had entered their chain linked paddock). At first they were simply jumping, then their behavior began to change to grabbing at the man’s shirt. At this point the owner waded in on the dogs, and they backed off. Had the owner not been there, the dogs could possibly have hurt the man. Individually, none of these dogs would have become aggressive.
The bottom line is, dogs in groups exhibit behavior a single dog will not. Pack behavior needs to be guarded against at all times, and it is vital that owners of multiple large breed dogs manage them so they do not have the opportunity to run at large.
Growing up back in Minnesota you could hunt for “feral” dogs and cats (although we never did). I heard many of the dogs still had collars on them - if they were pets out for a night with the gang or long-lost pets I don’t know. They would run the deer pretty hard.