The pace of change in society was "astonishing" and nothing could be taken for granted, Auckland Crown Solicitor and University of Otago law graduate Simon Moore said.
Mr Moore, a Senior Counsel who is responsible for the prosecution of all indictable crime in the Auckland region, was commenting in an address at a University of Otago capping ceremony at the Dunedin Town Hall on Saturday.
Mr Moore told about 430 graduates that he was starting a murder trial today.
The deceased was a policeman with "decades of frontline experience all around New Zealand", Mr Moore said.
The policeman involved was an undercover officer, Sergeant Don Wilkinson.
He had "survived the usual and expected dangers of being a cop: assaults, knife attacks, shootings".
"He had survived two extremely dangerous UN deployments in Lebanon and Afghanistan.
"He had faced enemy fire.
"And yet he died on a dark September night two years ago, face down in a quiet suburban street in Auckland, shot with an air gun he never saw after he had attempted to place a tracking device on a suspect's car.
"That wasn't the way he expected to die.
"That wasn't the way anyone who knew him expected he would die."
Mr Moore said nothing could be taken for granted.
"We need to make the very best of what we have for as long as we have it."
Reflecting on changing times, he noted that in 1967 an Otago University student had been suspended by university authorities for living in a mixed flat.
"He had no romantic connection with any of his flatmates.
"It was just that they were female and he was male and he needed a roof over his head before the rigours of a Dunedin winter set in.
"In 2010 it seems inconceivable that the university's disciplinary powers could be invoked for something which, viewed through today's social lens, seems so apparently harmless."
Only seven years after the suspension incident, mixed flats had become the norm.
At that stage during his student days, Mr Moore said he had been living in a mixed flat in Castle St and those who chose to live in single-gender flats were "regarded by most of us as a little bit odd".
Since then his own three sons had flatted in Dunedin and their flats had been male only.
"It's taken just a generation to come the full circle," Mr Moore said.
He urged students to adapt to change, and to "laugh a lot and most of all laugh at yourself".
