Major forensics failures in a government-run laboratory seriously compromised the police investigation into Shandee’s murder, one of Australia’s most respected DNA experts finds. After months examining the case for Shandee’s Story, forensic biologist Dr Kirsty Wright is convinced critical problems thwarted the lab’s ability to generate DNA profiles from crime scenes - potentially allowing a killer to get away with murder.

Dr Wright finds the lab couldn’t find DNA in a sample of blood, or trace DNA from John Peros in his own car. She says all the results in Shandee’s case need to be retested by an independent laboratory, and that doing so could uncover the killer’s DNA.

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