Yes there is mercy in that. And he's in Mass. He probably didn't have a gun due to stupid gun laws up there.
All you animal lovers that are screaming he is cruel; just how the hell do you think dogs were put down before reliable firearms? A hammer to the skull is HUMANE.
There is NOTHING wrong with taking personal responsibility for your pets and putting them down if you must.
“Berube told investigators that on July 13, about 4 p.m., he killed Spot by striking him in the head with the claw end of a hammer, and may have hit the dog two or three times.”
http://www.eagletribune.com/punews/local_story_170005522.html