The police officer who led the initial search for a backpacker missing in Byron Bay was inexperienced, missing vital training and would conduct the operation very differently with the benefit of hindsight.
Speaking at an inquest into the disappearance of Theo Hayez on Wednesday - the same day police announced a $500,000 reward for information in his case - Senior Constable Louis Papworth admitted he had only conducted two minor searches before the Belgian teen went missing.
Both were launched within hours of when the subject was last seen and both people were located quickly.
Sen Const Papworth said the magnitude, logistical considerations and complexity of the Hayez search - which began nine days after he was last seen on May 31, 2019 - made it vastly different to anything he'd ever done before.
It remains the hardest search he's ever been engaged in.
"Why were you personally selected to coordinate the first day of Theo's search?" counsel assisting the coroner Kirsten Edwards asked.
"I believe I was just the on-call rescue operator that day," Sen Const Papworth said.
He ended up with stewardship of the search over its first two days despite having no training in a mapping tool that allowed GPS data to be uploaded and searched areas accurately marked.
Sen Const Papworth and the search teams were instead forced to rely on paper maps and pens.
The search came with a lot of pressure from the get go, given time was running out to find the 18-year-old alive.
"I'm not an expert in timeframes of survival, but ... it'd been nine days. It was concerning," Sen Const Papworth said.
Due to the urgency of the search and his inexperience, he told the inquest he had made some mistakes.
His paperwork from the first day of the search wasn't up to its usual standard, he had no picture of Theo to hand to volunteers - who were instead having to recall the image they were shown at the beginning of the day - and he deployed volunteers without specific instructions of what they should look for in their search area.
He also sent teams into the field without GPS devices to log their movements on at least the first - and probably the second - day of the search.
"I've sort of got a belief now that if there's not GPS data, (in my eyes) that area hasn't been searched," he said.
Sen Const Papworth was also asked about another officer's evidence that she had texted him to suggest he ask for assistance from Queensland's police helicopter, which has thermal imaging capabilities that could help find a body.
He couldn't recall that text but, with the benefit of hindsight, would ask for that assistance, he said.
With the benefit of hindsight he would also have tried to find out more about Theo's interests and behaviours, to help tailor the search.
If he had access to location data sourced from Theo's phone on those first two days, the search would have looked very different too, Sen Const Papworth said.
The data showed Theo had spent seven minutes near cricket nets at a local sporting field, before charting a route through the Arakwal National Park to Cosy Corner Beach.
"If you'd had that access to that information, you would have approached the search in a very different way, and with a lot more intensity?" Ms Edwards asked.
"Yes, I'd agree," he said.
More volunteers would have been sent to those areas and he would have sent detectives to interview "vagrants" who were staying near the sporting field.
The inquest continues, and is due to hear new "significant" evidence on Thursday, Ms Edwards said.
