Yesterday marked the end of the second week of Coroner Alexander Ho’s inquiry into the 2019 death of 3-year-old Lachie Jones.
The boy was found face up in a Gore oxidation pond — wearing his favourite police outfit, including hi-vis vest — 1.2km away from his home and two police investigations determined he had drowned.
Until the hearing began, theories flew about potential foul play but Mr McKewen was the first to potentially give them weight.
On 29 January, 2019, he claims to have seen three people near the oxidation ponds where he was working.
Mr McKewen said one was small and wearing high-vis and he thought the others were teenagers, based on their size.
"I always thought it was significant," the witness told counsel assisting the coroner Simon Mount, KC.
"Were you thinking in your mind that the little person you saw ... might've been Lachie Jones?" Mr Mount asked.
"Could've been," Mr McKewen replied.
When Mr Mount asked him why he never told police, he said he would have needed approval from senior management, which he never requested as he was overwhelmed with work.
He said he wrote down more details about the sighting in a work diary, but threw it out when he moved house.
Lachie’s father Paul Jones never agreed with the police ruling that his son drowned and referred to the investigation as a "bloody police botch up".
He did not believe his son would run 1.2km alone, and jokingly described him as a "lazy little prick".
Mr Jones believed the police explanation lacked common sense and he had previously been worried about Lachie living with his mother, Michelle Officer, and her sons, Cameron and Jonathan Scott.
"I just have grave concerns [about] the way Lachie was treated in the last eight months; that something sinister’s happened," he said.
He also admitted he would get drunk and yell at Cameron and Jonathan.
"I take full responsibility for it ... I have, on numerous occasions, roared at those boys," Mr Jones confessed.
Multiple police officers involved in the investigation admitted the leadership structure was unclear.
Senior Sergeant Cynthia Fairley believed the officer in charge of the investigation was Sergeant Hua Tamariki, while he thought it was her.
Snr Sgt Fairley said Sgt Tamariki wanted to have the file as it was a "development opportunity".
But he said his policing career was heading in a different direction and he did not have the skill-set to lead the investigation.
He said while "OC" (officer in charge) appeared next to his name on some documents, that was not his role.
"I know how it could look in terms of what it says there, but ... it doesn't reflect on who was OC of the investigation,” Sgt Tamariki said.
Snr Sgt Fairley said she believed Lachie’s mother when she gave her version of events — that she was at a friend’s house and took her eyes off her son for a moment, by which time he was out of sight.
But Kimberley Rogers, a former friend of Ms Officer, described her recall of events as "bizarre".
The witness said after Lachie’s death, Ms Officer would speak to her about the night he disappeared.
She told the inquest Ms Officer was "chopping and changing" her version of events and she did not believe the boy had got away from Ms Officer.
"Well that's really bizarre because she was fit and strong enough to keep up with that little man ... it does not make any sense at all," Ms Rogers recalled thinking at the time.
She said following Lachie’s death she only saw Ms Officer become upset when Lachie’s coffin was lowered into the ground.
"I didn't really see any tears or any grief," Ms Rogers said.
She explained that three weeks after the toddler’s death she cut ties with Ms Officer "because of her lies".
The inquest resumes on Monday.
