The first phase of Coroner Ho’s inquest into the death of the 3-year-old finished last week after 13 days of evidence.
Due to health reasons, the public and media were excluded from the court while Constable Lachlan MacDonald gave his evidence.
A transcript of the evidence detailed how Const MacDonald’s dog Gee found Lachie’s scent about 40m away from his body.
The witness said after failing to obtain a scent on Grasslands Rd he arrived at the gate near the oxidation ponds.
He said he jumped the small fence next to the gate and lifted Gee over it.
"Upon arriving at the gate, I did not see Gee indicate or give any change of behaviour that would indicate to me a person had gone over the fence," Const Macdonald said.
He explained Gee was not trained to search for a specific person’s scent and could not, for example, be given a piece of Lachie’s clothing to know who to search for.
He said the amount of people who had been on Grasslands Rd searching for Lachie would have contaminated the area.
"Because of the disturbance from other people, the search I completed on Grasslands Rd was more about ascertaining if Lachlan was in the vegetation on the side of the road, rather than trying to track his foot and scent movements," Const MacDonald explained.
"At the time my primary focus was to locate Lachlan and observe anything Gee could show me to achieve this."
He was not sure if Lachie’s soiled nappy or bare feet would affect Gee’s ability to find his scent.
He also said he was not worried about the smell of the ponds interfering with the dog's capabilities.
The witness described the moment he pulled the toddler’s body from the water.
"He was on his back with his hands near his shoulder and his head was just under the water. His knees were just up out of the water," he said.
He said there was white foam coming from the boy’s mouth, which he cleared away before performing CPR.
Counsel assisting the coroner Simon Mount KC asked if there was anything about the body that might have indicated it had been in a freezer.
"No, I don’t think so. No, I don’t know. No, there’s nothing that stands out to me. It was a boy in a cold pond, that’s the way it came across to me at the time," the witness replied.
Counsel for police Robin Bates asked him about backtracking Lachie’s scent to establish a path he may have taken.
Const MacDonald explained it would have been difficult to backtrack because the area was contaminated.
"I had contaminated the scene by myself walking there," he said.
The inquest will continue in August when the court is expected to hear from expert witnesses.
