This case has some excellent insight into how a defense attorney finds a crack in a lab tech’s QA protocols [ she spit on a DNA sample] and then tries to blow up all the other work-product used by the Prosecution.
The evidence of interest is a single bullet with arguable DNA recovered from the scene 4 months AFTER the crime. Ooops.
The def attorney also uses a phone message from a cop to the crime lab gal.
From the news article: “The message, Buting [the defense attorney] pointed out, asked Culhane [the lab tech] to test evidence “to try to put” Halbach [the homicide victim] in Avery’s [the bad guy] trailer or garage.” Ooops.
http://www.jsonline.com/news/crime/dna-experts-record-ripped-b99643010z1-363819471.html
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This comes from the “Making a Murderer” series on Netflix – 10 hours of gut wrenching horror. In this part of the series, the Lab Analyst on the stand almost tears up as the Defense Attorney rips her a new one. IMO, she should have been arrested for destruction of evidence.