The incident occurred on Monday, November 9, in Greenbrier, Arkansas.
The investigator, identified as James Freeman, went to the home on Autumn Hills Rd. However the house he was meant to visit was two doors down.
As Freeman got out of his car, the dog - three-year-old Terrier mix Clide - started barking at him, FOX 16 reports. He fired one shot, killing Clide instantly.
A video taken by Clide's owner Chris Coiner shows him angrily confronting the investigator, who appears emotionless as he returns to his vehicle.
'You shot and killed my goddamn dog, you motherf****r,' Coiner screamed at Freeman, with the graphic video showing the dog laying bloodied and dead on the ground as a woman tends to it. 'Get off my property, motherf****r!'
Coiner continued to yell at Freeman, calling him a 'piece of motherf***ing sh*t' and a 'p***y.'
Coiner told FOX 16 that the shooting happened as his children were returning home from school.
'I was livid, I was livid with feelings and he didn't care one bit,' Coiner said.
'He did not make any attempt to get away from it, he didn't make any attempt to get back in his vehicle, all he did was shoot the dog because he was barking at him.