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