they identified a former convict, lucas anderson. >> on the night in question, lucas anderson was herelley medical center in san jose being treated for alcohol poisoning. so how could his dna have made its way from the hospital to a murder scene? >> the ambulance that transported lucas from san jose to be treated for the alcohol intoxication was then the ambulance that responded to the homicide. the pulse oxometer that measures your oxygen levels was put on lucas's finger. when they got to the scene of the crime was put on the victim's finger and the dna was transferred in that method. >> in the end, lucas anderson did five months in maximum security confinement based upon dna evidence that put him at the scene of a crime he was nowhere near. coming up, preparing to commemorate one of worldwar 2's most important battles. ♪ over there. send the word. ♪ send the word over there. >> we will meet the american trio who will perform at normandy beach on the anniversary of d day. >>> recapping a top story on al jazeera america. sergeant bowe bergdahl has been freed by captors in afghanistan.

but lucas anderson was here in san jose being treated for alcohol poisoning.so how could his dna have possibly made it from the hospital where he was unconscious to a murder scene. >> the ambulance that transported lucas to be treated for alcohol was the ambulance that went to the murder scene. the same oxygen level indicator was put on the victim's finger. >> reporter: in the end lucas anderson did five months based on dna evidence that put him at the scene of the crime that he was nowhere near. next week, michael, in oakland right across the bay where i am, a trial will begin of a suspect named curtis tucker, a convict being tried on a decades old murder on dna evidence alone. now that we know that the dna evidence can be tainted and can convict the wrong person we should rethink basing entire cases on that basis as well. >> it's fascinating and scary as well. jacob ward, reporting from san francisco. >>> once convicted, overturning a case can take years. one man's release took two decades, and he's hoping that dna testing will prove his innocence. >> we do

but on the night in question lucas anderson was here at valley medical center in san jose being treated for alcohol poisoning. how could his dna l have been able to go travel to the murder scene? >> the ambulance was the ambulance that responded to the homicide. the pulse ox ometer was put on the l victim's finger and it was transferred in that method. >> based on dna evidence that put him at the scene of a crime he was nowhere near. jacob ward, al jazeera, san francisco. >> and this week's episode of the system, looks at how one man's release from prison, the system, why airs 9 eastern, 6:00 pacific. >> knowledge roxanroxana saberi. >> europeans who want to be online, a being ruling bun by the european court of justice earlier this month. the court says people can ask search engines to rooive information abouremoveinformati. you put your name here your e-mail address here, down below you paste the links to the materials you want removed here and in the box below that you explain why you want those links removed and below here you need to upload a foad i.d., give your -- photo i.d., giv

they identify add former convict, lucas anderson. >> but on the night in question, lucas anderson wascenter in san jose being treated for alcohol poisoning. so how could his dna have made its way from the hospital where he was unconscious to a murder scene? >> the ambulance that transported lucas from san jose to valley med to be treated for the alcohol intoxication was then the ambulance that responded to the homicide. the pulse ox omty, the thing that goes on your finger to measure oxygen levels was put on lucas's finger and at the scene of the crime was on the victim's finger. the dna was transferred in that method. >> lucas anderson did five months in maximum security c confinement based upon dna evidence that put him at the scene of a crime he was nowhere near. >> problems with dna evidence first came to light in 1997 after an f.b.i. agent blew the whistle on a federal crime lab. the agent described what he called a pattern of flawed forensic that led to verdict being overturned in hundreds of cases. many from one agent in particular. it's also the focus of part 2 of al jazeera's