Two dogs were rescued and are now awaiting adoption at the Table Mountain Animal Center .
Police say they've been to the home repeatedly since last summer on complaints of loose animals and trash in the yard.
"There were some calls that we came out and addressed those issues with the homeowners regarding dogs in the yard and such but there was nothing ever to lead us to believe what was happening inside the house and the number of dead animals that were inside the house," said Susan Medina, Arvada Police spokesperson.
One woman who noticed an underfed dog in the front yard last August wonders why more wasn't done.
"Because if they would have done something six months ago, they probably wouldn't have found 15 dead animals," said Carol, who didn't want her last name used. "Maybe four or five, but for 15 dead animals in six months, that's a little hard to believe."