Late one Spring night in 1999, a drunk driver in a four-wheel-drive smashed head-on with a yellow Volkswagen, killing the woman inside.

Police believed the drunk driver had crossed onto the wrong side of the road, but relatively unskilled and inexperienced investigators were struggling to back the theory up.

Because of the lack of evidence, the man was acquitted of culpable driving causing death the next year, and he got off with a fine, a cancelled licence and a good behaviour order.

Sergeant Neit, now widely regarded as one of the country's most skilled crash investigators, reflected on the case last week, as he prepared to leave the force after 33 years.

Poring over photos of the crash scene, the expert noticed two tiny, inconspicuous marks on the left-hand side of the road, where police believed the victim's car had been on impact.

They used a forklift to flip the woman's Volkswagen, finding corresponding scratches underneath. It was evidence that strongly suggested the four-wheel-drive had crossed the road and come over the top of the Volkswagen, forcing its body down to scratch the surface of the road.

"It was too late to prove it," Sergeant Neit said.

"But for me that case has always stuck in my mind, in that the most insignificant piece of evidence can change the outcome of things."

It was a moment that would prove pivotal for the crash team.

Sergeant Neit and others went to the police chief, telling him things needed to change.

He was given the green light to travel the globe to learn from the world's best crash investigators, using the expertise to reshape the squad.

The Collision Investigation and Reconstruction Team, colloquially known as the "prang gang", is now considered to be among the best in the country.

Sergeant Neit is one of a group of departing ACT Policing veterans, many of whom have resisted moves to federal policing and stayed local, despite a perception it hinders career progression.

It includes the highly-respected detective sergeant Bob Wynn, head of the exhibit management centre Ashley McCammon, crime manager Robert Krajina, and media team leader Peter Brewer.

"There's about 150 years of policing experience going out the door this week," Sergeant Neit said.

"Sometimes it is a shame that it goes out the door and it is just lost."

An entirely different world existed for Canberra's police when Sergeant Neit decided to join up in his early 20s, one he believes was actually more violent, more rough-and-tumble.

He was working as a plasterer, and jokes "heavy sheets of gyprock … and my wife" were behind the switch to policing.

A local cop through and through, Sergeant Neit is known to most players in the small jurisdiction.

It's something he prides himself on. A badge reading "the sheriff" is still stuck to his office door, and his saying "the blood, the mud, and the beer" is known to many long-time colleagues who have come up the ranks alongside him.

"I joined to be the sherriff, so to leave policing and go into something maybe new, or not, is a little difficult," he said.

Over the years, Sergeant Neit has amassed as many tales of criminal hilarity as he has tragedy.

And he knows how to tell them.

He recounts one occasion, when he and his colleague Mark Scott were about to give a "snotty" young fellow a ticket while patrolling in Red Hill.

"He's looked at Mark, and said 'do you know who my father is?'."

"Mark's put his arm around him and said 'mate, that's a question for your mother'."

Another time, he recalls making the inexplicable discovery of a car half-submerged in a lake at 11pm, the partially undressed male and female passengers still inside as it slowly sunk.

"We asked what happened to his pants and her top," Sergeant Neit said.

"His comment was that he'd learnt in life saving that you should take your clothes off first before you swim back," he said.

"As we slowly watched his car floating out, and sinking … the question we asked was 'are you husband and wife', and we got 'yes'.

"So I've asked 'is that your husband and is that your wife', and the answer was 'not really'."

His plans? Work on his bowling game at the Tuggeranong bowls club.

"It's a bit sad when you're getting flogged by 80-year-olds," he jokes.

"But it makes you feel young, because they say 'ah, well done young fella'."

He still leaves a legacy within ACT Policing, and is immensely proud of having two sons in the force.

"I used to sit around the dining-room table and I used to regale my sons with stories of adventures from my work," he said.

"You really start to understand that your career is coming to an end when your sons sit around the table and regale you with stories … and you wish you were doing what they're doing."