Camper,
No... The dogs cannot enter the home without either the permission of the occupants or a search warrant. The dogs can alert at the door, telling their handlers that the scent continues with cues that they use. But just being at the front door and alerting, if it is not the home of the in-laws (who most likely would cooperate), could cause the evidence to be suppressed if their was no permission granted to be on the
property at all. These laws differ from state to state about how much latitude is granted police in dog searches.
In a case like this one, you don't
want the permission of the occupants. You want a search warrant, signed by a judge, that states specifically what you are looking for and how you intend to proceed. You want to dot all the "i"s and cross all the "t"s. Permission to enter by the occupants can be a legal mess if something of evidentiary value is found. A good defense attorney can get the evidence thrown out on a claim that the police misled the occupant about what they could search for.
No average joe killer holds a woman captive for even twenty four hours and then dumps her dead without her clothing with no signs that there was sexual assault. There seems to me to be only one scenario that fits that set of circumstances. The person who killed Stacy Ann was a woman.
Stacy Ann had been to this neighborhood a number of times before, since they had dated seven years, but her mother said "never by herself." I can relate to that. When my husband does the driving and has the directions I pay no attention to where I am or which way we are going. Much of his family lives in Pittsburgh and we have been married fifteen years. Though we've lived out of state most of that time period, I know I've been to Pittsburgh nearly once a year every year. I would no more know where I am going if I went there today than I did the first time we went. Pittsburgh is a big city, and Queens is a big city, and I was raised in a small one.
I'd be looking into Damien's past. His last known reaction to the press "I've got nothing to say"... sounds arrogant and not the least bit helpful. How many times was he is Queens without Stacy over the last few years? Did he have a serious girlfriend, a long term relationship, that broke up because of Stacy? Or maybe even not because of Stacy but because of his entrance into the marines, where he then met Stacy. Is there an old flame from the old neighborhood that could be a fry short of a happy meal and has pined away about him all this time? Or possibly he had come to Queens alone, without Stacy, recently, and rekindled the old flame... even if just for a night. It could have been something that was just a small indiscretion to him when he'd had one too many beers. But if the old flame is unstable it could have signaled to her that they were once again an item.
Damien is only 28 and Stacy was 26. If they have been dating for seven years they were quite young when their relationship began. So any relationship with a girl he may have had before that time would almost surely have been a high school sweetheart. It is not unusual for high school sweethearts to part ways come college time but remain friendly. And it isn't unusual for the former high school sweetheart to stay in touch with his or her first love's parents. Perhaps Damien's parents mentioned Stacy's trip, alone for the first time, to his old girlfriend from high school. They would probably think nothing of mentioning this. To them it would have been more than seven years ago the woman and Damien parted ways. If they had no reason to believe the woman was mentally unstable they might have told her the whole interary... including the unlocked door waiting for Stacy's arrival. It would be very low risk for the old girlfriend to simply come over and enter the unlocked door and wait for Stacy. If Mark had awoken and come upstairs... if the parents had arrived home early... it would most likely seem as if nothing sinister was amiss. After all, this is an old family friend. In a stroke of luck for her, no one interupts. Stacy comes in and is momentarily startled to see someone she doesn't know but might recognize from old photos (prom pictures etc.). She is most likely aware the family has remained friendly with this person so she isn't alarmed. The woman charms Stacy with "congratulations" and blah blah blah and convinces Stacy to go with her to see a nice bridal shop or something like that. No struggle in the home. Stacy is completely unaware that she is to become a victim. The woman drives her somewhere where she pulls out a gun and now has control of her.
Just a thought... a long thought...