Ok, I am going to get blasted for this but I am putting in my two cents anyway...
The dog did what dogs do, it protected its home. It appears the tennant knew the day they had to be out, and I would guess they thought they had until the end of that day to leave and probably didnt expect the owner and police to show up at 9 in the morning. The tennant appeared to lock the dog in the bedroom rather than have it run free throughout the house, maybe trying to side on the error of caution in case the homeowner did come in the home. I find it hard to believe the dog didnt bark when the home owner and police officer entered the house to begin with. :shrug: