Dateline | December 07, 2012
>>> a new day dawned in albuquerque that june morning in 2008 , and as the sun came up, katherine pierce realized she had been transformed. in just six days, she had gone from smiling newlywed to blood stained widow, and to possible suspect in the murder of her husband, scott .
>> you know when a husband or wife dies, it's very natural for police to at least look at the surviving spouse.
>> i knew something was coming. it wasn't unusual.
>> and soon, katherine was face to face with veteran albuquerque homicide detective , mike fox .
>> a brand new bride tells a story of some mystery man coming into the house and executing her new husband. that's got to set off alarm bells.
>> she was somebody we had to look at.
>> tell me about katherine pierce's demeanor.
>> she actually shocked me how well she was able to put it together.
>> calmer than you would expect?
>> detectives had many questions, especially after looking hard at the crime scene and finding something confusing. the killer had dumped out katherine 's purse on the back deck, but on the purse no fingerprints. so was this a robbery gone wrong or was the purse some kind of diversion?
>> we knew we were dealing with somebody at that point that gloved up with rubber gloves or something like that.
>> which says to you what?
>> tells me that whoever is involved was going in there to kill somebody and not leave any evidence behind.
>> burglars generally don't carry shotguns.
>> if somebody surprises them, instead of shooting them they just run away .
>> typically, that's what i've seen through my career.
>> even though the fact katherine 's purse was sort of dumped out and searched through, everything about this says planned murder, not planned burglary.
>> but planned by whom?
>> tell me about scott pierce . anybody didn't like him?
>> no. everybody liked him. great guy. nothing bad in his background at all.
>> you, no doubt, did your due diligence to find out whether that marriage was as happy as it appeared to be.
>> yes, talking to people around them, everything was fantastic.
>> but detectives had heard that story before. when they looked deeper, they learned katherine 's husband had a life insurance policy. the payoff in the mid six figure range, and she was the beneficiary. when they canvassed homes nearby, police found neighbors that heard a man and woman talking around 3:00 a.m . detectives wondered had that been scott and katherine ? within hours of her husband's murder, the criminalists confiscated the clothes katherine was wearing when she said her new husband was gunned down in front of her.
>> police took the clothing to test it.
>> everything was evidence at that point, i understand that.
>> you weren't concerned.
>> not at all. the detective asked me if i killed my husband.
>> straight out.
>> and i said no, and he seemed fairly satisfied with that.
>> but detectives asked katherine to run through her story again, looking for inconsistencies. so she went through what happened that night again, just as she did in this video, she would later make for her attorneys.
>> from here i turned around and there was a person, tall person standing here. so i said oh, scott , stop messing around. and then he said get down on the ground. that's when i knew somebody was in my house that didn't belong. i saw scott standing at the other end of the room. i held out my hand and i said scott , wait. the gun went off. his head was right here. and his neck was blown open, all of this, his throat, everything to back here, it was just gone.
>> did she say or do anything that made you suspicious?
>> no. nothing showed she wasn't telling the truth. but unfortunately in her situation i have to go after her as a possible suspect. it's to find out if she is involved, a, and then b, if she's not, later on make it so when this does go to trial it's not brought up by a defense attorney that tries to throw it on her, make her look like she's the one that did it.
>> but remember, there was something katherine heard on the kitchen floor that night, something that came from that shadowy figure that held a shotgun to katherine 's head before firing the fatal shot at scott . the killer had also asked her a question that would soon become the focus of this investigation.
>> he said where's manny .
>> manny .
>> and i said what? what did you say? and he said where's manny .
>> it was a name that meant nothing to homicide investigators. but katherine pierce says she knew exactly who the man was after. now police were looking for him, too.
>> so who was this mystery man named manny and could he help break this case?
>> it didn't quite seem right this random person just happened to break in.
>> police are getting closer when "dateline" continues. [ male announcer