Associate Law Professor Scott Optican on the legality of court evidence obtained by different undercover policing techniques in New Zealand. A highlight of Auckland University's Raising the Bar 2021.

Listen to Assoc. Law Professor Scott Optican on the legality of different undercover policing techniques in New Zealand.

Covert policing techniques from the USA you see in the movies or on tv don't necessarily translate to this country. Take the example of a detective getting hold of a glass from a bar which has been used by someone who has finished a drink. The DNA traces its contains - perhaps from fingerprints or traces of saliva - can be used in court in the USA, according to Assoc. Prof. Scott Optican.

"In the United States, courts have squarely held that there is absolutely no problem with this kind of surreptitious police collection of DNA evidence. American judges have stated that once a subject has abandoned his DNA on a bar glass, discarded tissue or the like, they have no further privacy or possessory interest in it, and so no rights to protect. Hence its collection is just fair game for the police or anyone else."

In fact, based on this very abandonment theory, Optican adds, "Just last month, detectives in Colorado recently reinvigorated a 35-year-old murder cold case. They did this by getting on the same aeroplane as the suspect, sitting a few rows behind him, and intercepting a discarded water bottle that he drank from before the flight attendant at Spirit Airlines could throw it in the bin. DNA evidence obtained from that bottle matched DNA evidence taken from a ski mask worn by the killer and preserved all these years later in a police lab. "

That suspect is now facing prosecution for the 1985 murder as a result of that very simple sting.

"So, he asks, "What about the propriety of the bar glass scenario in New Zealand? Its status is currently unsettled in New Zealand law. It's never been tested through a New Zealand court. And that's probably because it hasn't been used by the police as a way of obtaining a criminal suspect's DNA. In fact, there is no specific body of New Zealand law that governs the legality or not of DNA evidence obtained by police in this manner."

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