There are details concerning actual location of dog when shot (property of shooter or not, renting I think does not matter) and what dog was focused on (shooter, livestock, another dog, the moon, etc.). I am guessing there is evidence on scene that peaked interest of shooter. Threat level of dog to shooter difficult to assess so may have to rely upon local assessment or opinions of dog by community (the village). No indication dog was attacking or otherwise threatening shooters dog. Was lab in act of trying to get at roosting chickens, chasing / mauling chickens, or among carcasses of mauled chickens? Two more things make this a tough one; first was there prior discord between shooter and dog owner (then dog in the middle), and the attempt at S-S-S where evidence was hidden? Law enforcement is going to see S-S-S as an attempt to hide something from them as well.
In my setting where I did a some dog depopulation, the first done when noted dog problem was find out who dog belonged to. That involved doing some walking and talking in a radius that exceeded 1/2 mile. Here I had to get talk to multiple parties to find some in the know and also could recall that some parties were not factual. Once owner located I informed them of what dog(s) did and I informed them what I reluctant but otherwise prepared to do. Most owners then worked to improve control over dog(s) and we often exchanged phone numbers. I got to know most of my current neighbors because of dog issues. Some owners not so nice and those usually had less than ideal relations with other neighbors. If dog returned I tried to call owner immediately, if dog was going after my birds I would engage dog and run it off although most of time did not have rifle. Then called owner which more often that not paid for losses and attempted to improve containment. Dogs shot came in more than twice killing birds and had a weapon ready as pattern / time of day established. Another point I must indicate is I informed police (county) that I had a dog problem before I resolved shooting it. When dog shot I informed police immediately. Owners informed later. This replicated here only twice. In first instance neighbor not only gave me money to cover birds lost, he gave me enough to repair extensive pen damage without even looking at it. He had more dogs so I worked on training those a bit whick proved easier than mine to come later. Other guy proved to have more serious dog related issues and was eventually forced to leave. He was prone to tell whoppers and had a history of dog issues, some even with me that involved dog being aggressive. My accusation alone did not help because we developed a "history", other neighbors had to come forth with similar stories which did occur.
