The Alexandra-based senior constable recently took part in his daughter Ellen's graduation as a member of the Victorian police, in Melbourne.
He sought permission from the New Zealand and Victorian police and was allowed to wear his police uniform while presenting his 27-year-old daughter with her certificate of identification - her police badge and wallet photo ID - during the ceremony.
''It's one of those moments I'll never forget,'' he said yesterday.
Snr Const Colligan believed it was the first time a New Zealand police officer had taken an active role in an Australian police graduation ceremony in such circumstances, in uniform, and said it added even more emotion to the occasion.
''It was very moving and very humbling and when I handed over her badge, I had tears just rolling down my face.''
Victoria police Deputy Commissioner Tim Cartwright was officiating at the ceremony and shook the hands of both Colligans after they saluted him.
''He leaned over towards me and said, 'There's no shame in being in tears at an occasion like this one'.''
Snr Const Colligan has been a policeman for 32 years, starting his career in Invercargill and serving the past 20 years in Alexandra.
His daughter, the eldest of his four children, has mostly worked as an office manager since moving to Australia five years ago.
''Then she phoned me one day and said: 'Dad, I'm going to try and join the police here', so I was pretty chuffed about that.''
She made it through the screening process before being called up for training in July last year.
After 33 weeks' of training, she completed the course and graduated on March 21.
Victorian police are armed and she would no problem dealing with that, her father said.
He has served as the national vice-president of Pistol New Zealand and his daughter was familiar with the use of firearms.
She will spend her first months as a constable on the ''booze bus'' working in and around Melbourne and then work at Caulfield Police Station before getting a permanent posting.
Snr Const Colligan said it was a privilege to be involved in her graduation and he was ''proud as'' of his daughter.
She would remain loyal to her home country, he said.
''She might be living in Australia but of course, she'll still be an All Black supporter.''
