It was an emotional day for police dog handlers who have lost their dogs in the line of duty, as a new memorial wall was unveiled.

A special ceremony was held at the Police Dog Training Centre in Trentham on Wednesday afternoon as the Wall of Remembrance was revealed.

There are 24 names on the wall, a name for each dog killed since 1972.

It has been nearly a year since the most recent dog to be killed in the line of duty, Gazza, was shot.

His handler, Constable Josh Robertson, spoke publicly of his loss for the first time.

He said it was an emotional day, there was a lot of closure but it also brought up what happened.

"It is not something you just get over when you get another dog, it takes time. Time does heal but it is always there, a bit of an open wound."

Constable Robertson said he still thinks about Gazza every day.

"He was a very driven, very loyal dog and outside of work he was a very playful, soft and loving dog, an allrounder really," he said.

Associate Justice Minister Mark Mitchell also acknowledged Gazza's death.

The former police dog handler said when a police dog is killed there is a huge outpouring of emotion and feeling from the public.

He commended Constable Robertson who is out on duty again with a new dog, Iko.

"I know you have just rehandled a dog and you are out back on operations, so well done." He said.

Iko is also a special feature of the new memorial wall, with two cut-out photos of the dog in action alongside the names of those killed.