Chief Insp Lock has spent two months at the Dunedin Central Police Station, filling in for Inspector Alastair Dickie who is relieving in Central Otago.
A career policeman, Chief Insp Lock has filled many of the South Australia Police's top positions since graduating in 1976.
He has been in charge of uniformed operations in the Sturt local service area for the past 12 months, responsible for five police stations and a watchhouse in the southern metropolitan area of Adelaide with a population of about 360,000.
He spent 20 years in the Special Tasks and Rescue group, which had a combined focus on anti-terrorist activity, search and rescue and high-risk crime.
Originally from the South Australia city of Mount Gambier (population 24,000), he sacrificed a rural lifestyle to rise through the ranks professionally.
He spent two years in charge of recruiting for the South Australia Police, led the equity and diversity branch and was made a chief inspector in 2006.
The secondment to Dunedin is his first stint in the South Island, which he says is "absolutely brilliant".
South Australia Police offer secondments to Kent in England, Singapore and Hong Kong as well as New Zealand.
In the decade of secondments with New Zealand, about 10 senior officers from each country have temporarily swapped offices.
Chief Insp Lock has made the most of his new surroundings, recently taking his family to ski in Queenstown. His wife Sue, a sergeant with the sex crime investigation branch in Adelaide, and their 12-year-old son Harry visited during the South Australia school holidays.
Getting sunburnt on the snow was a novelty experience, especially for his son who had never seen snow before.
Crime in Dunedin was similar to that in South Australia, although the technology available to New Zealand officers was superior, he said.
Systems used in the central Dunedin station have inspired Chief Insp Lock, who has written a list of potential improvements to trial in Sturt.
"New Zealand police have implemented some great technical processes to allow more staff on the frontline," he said.
He was thankful for a "brilliant" bunch of staff at Dunedin in helping make his visit one of mutual benefits.
The future of policing in New Zealand and Australia would be driven by greater community involvement and use of the internet, he said.