While retreat and avoidance may be necessary for safety, they teach the dog that aggression is successful at removing the threat (negative reinforcement).
Further, if every time a person with a "white coat" enters the room a family member tenses, tightens on the leash or scolds the dog, or you or your staff show fear or anxiety, this communicates to the dog that the white-coated person is a threat. Furthermore if the growling has been suppressed by punishment and the aggression has successfully caused you or your staff to retreat, the dog may learn to bite without warning. This is not a control or pack leadership problem or due to the dog being "spoiled" — educate clients about learning principles and methods to alleviate the dog's fear.
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