Mystery surrounds the disappearance of Tauranga City Lotto Store co-owner John Duff 15 years after he failed to turn up to work. Kristin Macfarlane spoke to the police officer in charge of the case and Duff's stepdaughter, who would love some closure after all this time.

Each time the stepdaughter of missing Lotto man John Duff learns a body has been discovered her heart "skips a beat" and she hopes it's the day she finally gets closure after 15 years.

That closure has never arrived, and the disappearance of Duff remains a mystery after he was last seen on June 22, 2003. Duff, co-owner of the Tauranga City Lotto Store on Grey St, was 54 when he went missing and his case remains open today.

Jane, Duff's stepdaughter from a previous long-term relationship, was his only family.

"It seems like such a short time but such a long time," Jane says.

"It still seems really current because there's no closure.

Jane says any time a body is located she gets a little bit of hope that it might be the closure she is seeking.

"Your heart always skips a beat, and I wonder if this is going to be our closure."

Jane was 12 when she met him and just before he was reported missing, Jane was getting ready to announce her first pregnancy.

"Our children never got to meet him, they know who he is, they know that he had meaning in my life."

"He would have made a very good grandfather; I would've welcomed his input."

If Duff's disappearance was not by his own will, Jane urges people who may have information about his disappearance to "find your own peace, give it to the people who need it".

"Is it their right to hold on to it? Do the right thing for themselves and for John."

She says the officer in charge of the case - Sergeant Trevor Brown - told her right at the beginning that he "wasn't going to drop this", and Jane is pleased he had kept his word.

Brown says when people go missing there are usually three possible scenarios.

"With any missing person there are the three scenarios: murdered, committed suicide, or he decided to disappear of his own free will," Brown says.

After thorough investigations, police can often rule out infeasible options and conclude a case even without a body, or an offender.

In Duff's case, Brown says police have been unable to rule out any of the three because each one is possible.

Sergeant Trevor Brown from the Tauranga Police would love someone who knows about John Duff's disappearance to come forward. (Photo / John Borren)

"It's a real mystery," Brown says.

"Like with any investigation when you delve into it, there were reasons for all three. [Police] have investigated the three. There's a plausible case for each," he says.

Friends and family became worried when Duff failed to turn up for work. His home was unlocked, his bed had not been slept in, and his car was in the carport. His bank account has never been touched.

Brown says there was no disturbance at his home in Matua.

"All enquiries, we never placed him away from the house. He was sitting at his computer at 1am."

He was last seen while walking with his former partner and business partner Kerry Tuck.

They had discussed Duff buying her share of their business. He agreed to go to the bank to inquire about borrowing money to do so, but he failed to turn up for work the next morning.

Brown says police checked CCTV coverage, but there wasn't the same coverage as there is today.

Just over four years after he disappeared, Coroner Michael Cooney declared Duff dead.

However, he asked the police to retain Mr Duff's file.

"He clearly wished the file to be open," Brown says.

"It's very much an open file. It's the unknown; there's no body."

"It would be great for everyone to have a definitive answer for it ... whether it comes tomorrow or in a couple of years.

Brown believes foul play is a definite possibility in Duff's disappearance and says, in historic murder cases, loyalties can change over the years prompting someone to come forward. If so, he would love to talk to them in confidence.

"It would be absolutely amazing for the family and the number of people connected with John.

"You're either a person who can leave it at the door or not."

"For me, I would like to end the investigation; we'd like to have some conclusion certainly for those connected ... they would like to at least know."

Brown says Duff did not have a large circle of friends.

"A lot of people knew who he was, most of the city-goers knew him as the Lotto man."

He worked on the toll bridge where he had met Tuck before they bought the Lucky Lotto shop together.

"He lived a very sedentary life. The shop was basically his life."

Over the years there have been sightings of Duff.

The first came a couple of days after his disappearance when someone who knew him thought he recognised him in Rotorua and was 99 per cent sure it was him. The witness said hello but there was no interaction, Brown says.

Duff did have connections in Rotorua.

There have also been some "loose sightings" of Duff in the South Island and overseas.

Brown says a couple of travelling in Europe says they saw a person they both believed was Duff in France and came forward after some publicity about the case about five years ago.

He says the couple was familiar with Duff but "unfortunately, they didn't approach him".

Initially, you get a lot of reports, but as time goes on those reports diminish, Brown says.

"We would certainly follow up any further information."

Brown says it is not uncommon to get personally invested in cases and he would love to bring closure for Jane and those close to Duff.