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a security camera captured images of a
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19 year old girl as she was abducted
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from a convenience store
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forensic scientists needed to find some
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way to improve the images for possible
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leads
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and the scanning electron microscope
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eventually identified the trail
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of the missing girl
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[Music]
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moose lake minnesota
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one of the many reasons why the state is
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known as the land of ten thousand lakes
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[Music]
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this small town outside of duluth was
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home to 19 year old katie poyer
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[Music]
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interest included her family several
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sports and her pet dogs
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[Music]
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after graduating from high school in
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1998
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katie studied criminal justice at a
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nearby community college and also became
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engaged to her boyfriend mark
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katie worked as a clerk at this moose
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lake convenience store
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a job her mother didn't want her to take
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deviance that would come in there and
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she'd just say oh mom you know don't
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worry
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and you know that's how she was very
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trusting
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trusting
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person
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one night
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around midnight when katie was working
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the night shift alone a customer called
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police to say that the store was open
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but there were no employees around
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are you talking about the conoco station
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police went to investigate
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there were no signs of violence and no
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money was missing from the cash register
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or the safe and katie's car keys were
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still there
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on the counter were notes with money
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from customers who had purchased items
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sometime after katie left the store
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police wondered whether katie might have
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left the store with a friend
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was there anybody close to her in her
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family that may have come and taken her
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either
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as a prank
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or
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um for some other purpose i never
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thought that she left on her own
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and she would have never done
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the store had four security cameras
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focused on various areas
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at 11 38 pm
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the security cameras revealed a
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caucasian man forcing katie out of the
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front door into the parking lot
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the pictures were grainy
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and showed few details of the abductor
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there were no security cameras outside
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the store to photograph the getaway
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vehicle
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the store was located near a major
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highway which meant the kidnapper could
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have left the area at high speed
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a search of nearby streets and parks in
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moose lake was fruitless
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neighbors near the store told police
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they saw a black pickup truck circling
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the area before katie's abduction
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and an employee at the sandwich shop
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next to the convenience store told
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police she had seen the same black
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pickup truck in the parking lot about
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three hours before katie vanished
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she said the driver was glaring
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inappropriately as female customers left
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the store
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on a hunch
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the employee wrote down what she could
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remember of the license plate
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she said it was a minnesota license
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plate and that the first three digits
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were five five seven
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she also recalled that the last letter
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on the plate was a y
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police hoped that if they found this
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black pickup truck
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they would also find
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katie poyer
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[Music]
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minnesota national guard helicopters
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searched the area for 19 year old katie
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poyer
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on the ground
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dozens of community volunteers joined
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police in the search
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but with each passing day
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and no word from the kidnapper hope
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started to fade that katie would be
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found alive
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[Music]
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police searched their database for black
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pickup trucks registered in the state of
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minnesota with a license plate beginning
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with five five seven and ending with the
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letter y
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surprisingly there were hundreds of
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vehicles matching that description
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[Music]
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surveillance video captured images of
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the man who abducted katie from the
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convenience store
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the quality of the pictures was poor and
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the images too distorted to clearly
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identify the kidnapper
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to improve the pictures police sent the
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tapes to nasa which has many years of
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experience trying to improve pictures
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sent from space
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solar physicist dr david hathaway
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created a process to enhance video
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images called this our
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dr hathaway says
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a video picture is really two different
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fields that create one picture
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these two fields change so rapidly the
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human eye can't discern it
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dr hathaway combined the even and odd
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frames so that both could be viewed at
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the same time
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creating twice the number of lines of
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resolution
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[Music]
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in one of those freeze frame images
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dr hathaway was able to isolate the
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kidnapper
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when he removed some of the grain in the
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picture he could see that the man had
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short blonde or gray hair was
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approximately five feet ten inches tall
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with an average build and he wore a dark
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new york yankees baseball jersey with
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the number 23 on the back
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unfortunately even this new technique
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could not produce a clear image of the
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kidnapper's face
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but using what they had a police sketch
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artist released a rough drawing along
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with a physical description including
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his clothing to the media
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hundreds of tips poured into police
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one of those tips led to donald dean
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christensen who had a past conviction on
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a sex offense
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christensen had been free at the time of
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katie's abduction
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donald dean christensen had several
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tattoos including a large one on his
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left forearm
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but the security camera video revealed
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the kidnapper had no tattoo on his
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forearm
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christensen was cleared
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[Music]
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three weeks after katie's abduction
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dispatcher paula francisco answered a
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telephone call from a citizen who had a
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tip
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it was lead number 1960
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the caller worked at the minnesota
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veterans home in minneapolis and was
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suspicious of a janitor there who had
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just quit
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his name
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was donald albin blonde
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the caller was suspicious because blom
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changed his appearance around the time
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katy poyer disappeared
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[Music]
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married and the father of four children
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a background check showed that blom had
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prior convictions for assault rape and
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kidnapping dating back to the 1970s
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his last conviction was in 1983
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when blam had forced two young women
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into the woods at knife point and tied
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them to a tree
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fortunately the girls escaped before
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they were assaulted
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but a check of motor vehicles revealed
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blom did not own a black pickup truck as
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witnesses described
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[Music]
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police hoped a search of blom's home
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would be far more revealing
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[Music]
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when police descended upon the home of
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donald blom
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they found no trace of katy poyer
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[Music]
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blom said he was innocent and that he
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had an alibi for the night of katie's
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disappearance
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when investigators learned blom owned
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vacation property near moose lake
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they searched there too
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[Music]
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once again
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there was no sign of katie
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but investigators noticed a large fire
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pit next to a trailer on the property
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technicians sifted the fire pit for
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trace evidence and found several small
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items that appeared to be boned
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their daughter
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police asked a forensic anthropologist
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dr susan thurston meister to examine the
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fragments
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she says human bone differs from animal
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bone
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the cross section of human bone has a
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circular pattern animal bone is linear
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[Music]
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dr meister examined the human bone
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fragments to determine the age and sex
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of the victim
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this part of the pelvis called the pubic
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symphysis was key
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the bone had an obtuse angle
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greater than 90 degrees indicative of a
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female
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and the oval surface was heavily ridged
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characteristic of a young adult
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skull fragments also helped determine
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the victim's age
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the joints or sutures of the skull bones
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were open
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skull sutures typically close around age
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35.
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dr meister concluded the remains were
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those of a young woman
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[Music]
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while the findings were consistent with
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katy poyer it was far from a positive
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identification
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the bones were too badly damaged for dna
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testing and collectively represented
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only 25
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of a human skeleton
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at the time
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[Music]
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but several tooth fragments also were
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recovered from bloms fire pit
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investigators called in forensic
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odontologist dr ann norlander who
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specializes in making identification
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based on dental x-rays
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this tooth
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was the largest and most intact of those
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recovered
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identified the tooth as human
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when she compared to katie poyer's
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dental records she saw that the shape
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and size were consistent with katie's
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lower left second molar known as tooth
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number 18
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and she noticed something else what
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looked to be
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remnants of a filling in the tooth
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dr norlander asked forensic scientists
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at the minnesota bureau of criminal
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apprehension to conduct an analysis of
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the filling
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forensic scientist mark nielsen used a
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scanning electron microscope to magnify
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the filling so that it was thousands of
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times
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to larger determine what the elemental
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composition is of the particular
00:15:30
substance that we have
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within the sample chamber
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the microscope bombards an isolated
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section of the sample with an electron
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beam
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and different elements will react to the
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beam differently
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[Music]
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so the type of x-ray will reveal the
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elemental composition of the sample
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the result showed that the filling
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material in the tooth was highly unusual
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it contained zirconium and silicon in
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concentrations that they had never seen
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before in dental cement
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when scientists contacted katie poyer's
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dentist dr melanie meyer
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she told them something interesting
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her records indicated she had replaced a
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filling in katie's tooth number 18 two
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weeks before the abduction
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dr meyer said
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she used a brand new material not yet on
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the market to fill her tooth
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the material was a sample called rely x
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arc
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which had been given to her at a dental
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conference
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[Music]
00:17:01
dr meyer told investigators that rely x
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was manufactured by the 3m company
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headquartered in minnesota
00:17:09
when contacted by police
00:17:11
chemists at 3m said that rely x
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contained concentrations of two elements
00:17:18
zirconium
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and silicon
00:17:21
the same materials
00:17:23
in the same concentrations that were
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found in the tooth in donald bloms fire
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pit
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of katie
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[Music]
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in a garage on one of donald blom's
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properties was the black pickup truck
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with the same license plate police were
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looking for
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state records listed blom's truck as
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white
00:17:59
a clerical error
00:18:02
donald blom was arrested
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and charged with katie poyer's murder
00:18:10
[Music]
00:18:20
when confronted with the scanning
00:18:22
electron microscope findings
00:18:24
blom confessed to katie's murder during
00:18:26
a taped conversation with special agent
00:18:28
phil wagner
00:18:35
[Music]
00:18:42
admitted to kidnapping and killing katy
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poyer
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[Music]
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[Music]
00:18:55
[Applause]
00:19:00
[Music]
00:19:05
foreign
00:19:08
[Music]
00:19:16
but two weeks later
00:19:18
donald blom recanted claiming the
00:19:21
confession was coerced
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prosecutors know that blam was in the
00:19:27
vicinity of the convenience store that
00:19:28
day because his credit card receipts
00:19:31
show he purchased liquor nearby around 5
00:19:34
pm
00:19:36
the sandwich shop employee saw blom
00:19:38
leering at customers in the parking lot
00:19:40
around 8 p.m three hours before katie
00:19:43
was abducted
00:19:45
blom may have seen katie then and
00:19:48
returned at 11 30
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entering the store when she was alone
00:19:53
prosecutors explained the scientific
00:19:55
evidence to the jury especially their
00:19:58
smoking gun
00:20:00
the dental filling material in the tooth
00:20:02
identified as katie's
00:20:04
a material which was so limited in
00:20:07
distribution it wasn't yet on the market
00:20:11
the jury understood the scanning
00:20:13
electron analysis
00:20:16
donald blonde was convicted of
00:20:18
first-degree murder and was sentenced to
00:20:20
life in prison without parole
00:20:26
the verdict
00:20:27
is little solace for the players
00:20:36
[Music]
00:20:55
as a result of this case
00:20:57
minnesota lawmakers passed katie's law
00:21:00
which includes stiffer penalties for
00:21:03
convicted sex offenders and mandates
00:21:05
better ways for police to track past
00:21:08
offenders
00:21:10
and the conoco chain that employed katy
00:21:12
poyer
00:21:13
now requires that at least two workers
00:21:16
are on duty each shift
00:21:23
[Music]
00:21:39
[Music]
00:21:45
[Music]
00:21:48
um
00:21:49
[Music]
00:22:04
[Music]
00:22:13
[Applause]
00:22:18
[Music]
00:22:27
[Music]
00:22:36
you
