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DNA extracted from the boots and jeans of slain hitchhiker Birgit Brauer could have come from the man accused of killing her, any of his paternally-related male relatives, or any male member of the population, a High Court jury heard this morning.
American forensic scientist Rachel Cline - giving video-link evidence from the US - told the New Plymouth High Court Miss Brauer's alleged killer Michael Scott Wallace "could not be excluded" as the source of the trace male DNA samples recovered.
But the testing - which searched only for male DNA, not for that of a specific person - yielded only a "partial profile", returning DNA evidence from five of 12 "sites" on Miss Brauer's boots and laces, and from two of 12 sites on the cuffs of her jeans.
Police say Wallace, 46, murdered Miss Brauer at Lucy's Gully, southwest of New Plymouth, on September 20, 2005.
It is alleged he bashed her repeatedly around the head, then stabbed her through the heart, after picking her up as she hitchhiked from Wanganui to New Plymouth.
Wallace - a firewood cutter from Himatangi, near Palmerston North - is denying the charge.
Ms Cline - who took the affirmation by video-link as the hearing began - said additional samples from the fly area of Miss Brauer's jeans were also analysed, but no DNA was found.
The DNA samples were sent to the US for analysis as the technology to examine them was not available in New Zealand.
Under cross examination by defence counsel Susan Hughes, QC, Ms Cline conceded that the smaller the quantity of DNA, the more likely it is to have been deposited by casual contact.
Trace DNA samples could have come from larger samples that had broken down over time, she said.
The samples from Miss Brauer's jeans and boots had been held for up to a year in New Zealand before being sent to the US for testing in August last year, the court heard.
