Jill Meagher: Conviction documentary reveals how killer Adrian Bayley was caught.

By Chloe Brice.

It took six days to catch Jill Meagher’s killer, about six hours for him to confess, and six minutes for a judge to remand him in custody.

But before notorious rapist and murderer Adrian Bayley was locked up, Jill’s husband Tom Meagher, while coming to terms with the highly publicised disappearance of his wife, became suspect number one.

In a new ABC documentary which delves inside the 2012 murder case, detectives admit to the “awful” treatment of Mr Meagher in the early stages of their investigation.

In the week following the Melbourne ABC staffer’s disappearance, police conducted a swift investigation that removed a potential serial killer from Melbourne’s streets and reunited Jill’s family with her body.

But initially detectives zeroed in on Mr Meagher — a “necessary” move but one which still troubles homicide detective David Butler.

"When you think about it down the track, you're left thinking 'Jeez, we were pretty awful, for the way we've treated this poor guy'," said Sergeant Butler, who led the investigation.

"Not only has he lost his wife, but now he's been treated pretty badly by us in some respects."

Mr Meagher routinely fronted the media, appealing for information on Jill and at one stage thanked investigators, despite their handling of him.

"I just wanted to say very briefly that despite the fact that this is the worst thing we'll ever go through in our lives, I've been really humbled by the support of the Australian public, the tireless efforts of the police and all the friends and family who've put their lives on hold to help us out," Mr Meagher said after Bayley's arrest.

Sergeant Butler said Mr Meagher's words that day were unforgettable.

"The lasting memory for me were the comments by Tom on the steps of the Magistrates Court, where he thanked us for our tireless efforts in solving the case so quickly, which in missing person cases is absolutely, absolutely critical," he said.

Acting Senior Sergeant Sharon Darcy said Mr Meagher was "amazing in the way that he was able to forgive" police.

"He appreciated the work they were doing and held no malice towards the way they had done their job," she said.

Phone tracking key to clearing husband and finding killer.

Sergeant Butler said Mr Meagher was quickly ruled out as a suspect.

"We were able to eliminate Tom reasonably quickly in this case. And the important thing with that was, let's say we never solved the case, the important thing with that is that we can front the media and we can say 'listen, it's not him, we've proven beyond any doubt that it's not him'," he said.

"And so excluding somebody is as important as finding the actual killer, in my view."

Phone tracking was crucial to eliminating Mr Meagher as a suspect, and later attaching Bayley to the whereabouts of Jill that evening and subsequent morning.

At 4:30am on Sunday, September 23, 2012, Mr Meagher's phone was on Sydney Road in Brunswick and Jill's phone was on the Tullamarine Freeway near Moreland Road.

Knowing this, and after a forensic search of Mr Meagher's apartment, police were satisfied he was not responsible.

The evidence Bayley could not explain.

It did not take long for investigators to shift their focus to Bayley — a notorious sex offender who had decades-long history of rape and violence.

Police knew they had "precious little time" to catch a violent criminal they thought was "probably unlikely to stop".

CCTV footage from outside a boutique along Sydney Road showed a brief interaction between Jill and her killer, and would lead police to Bayley.

It also directed detectives to two pieces of key evidence Bayley said he could not explain, and another that would ultimately force the "confident" killer to confess.

Bayley's car showed up on a toll transaction on Moreland Road at the same time Jill's phone was travelling through that area.

Police said this was the first piece of information that indicated Bayley could be their man.

Secondly, investigators traced the movements of Jill and Bayley using phone tracking and were able to plot them on the same path.

Both mobiles reached Gisborne, where Jill's body was later found, but only one phone returned — Bayley's.

Confident killer loses his cool.

Police searched Bayley's house while they interviewed him, and uncovered a vital piece of the puzzle — Jill's sim card.

Homicide detective Paul Rowe, who conducted the interview, said it appeared Bayley thought he would get away with his crime.

"He's a very confident person, to the extent that he was quite relaxed initially," Sergeant Rowe said.

Bayley insisted he had argued with his girlfriend while in the city on the night Jill went missing, then spent two hours looking for her, before eventually going home.

"I'm worried about women, women shouldn't walk around on their own", veteran homicide detective Ron Iddles, who listened to the interview over the phone, remembered Bayley saying.

As Sergeant Rowe asked Bayley about the photo of his car and the whereabouts of his phone, the killer's confidence began to erode.

"I can't explain it," became his go-to answer.

"There's a definite point in the interview where I could see his attitude, his demeanour, even his complexion change," Sergeant Rowe said.

"He became rattled — at one point in time he became angry."

When asked about the sim card, Bayley said: "I don't want to explain it."

"He sat back on his chair, he paused and he slightly shook his head," Sergeant Rowe said.

Before too long, Bayley admitted he was responsible, but did not divulge how he had committed the murder.

Police then spent two hours with him in a car as he led them to the exact location of Jill's body.

Two forensic investigators never returned to work.

Beyond the headlines of a case that triggered a national outpouring of emotion were the personal journeys that underpinned the search for Jill.

"She was a young woman, simply going about engaging in ordinary activity and died in that process," retired Supreme Court judge Frank Vincent.

These were the reasons the case so powerfully resonated with the public, he said.

Three days after Bayley was charged, 30,000 people staged a now-iconic march down Sydney Road in Brunswick, to remember Jill and to reclaim the night.

The emotional toll was so great for some close to the case that two forensic investigators, who attended the scene of Jill's body, never came back to work.

Sergeant Iddles said his former colleagues, Sergeant Butler and Sergeant Rowe, both struggled after the investigation, with Rowe eventually deciding to leave the homicide squad.

"The investigation is obviously very intense. For me personally, you know, I go home at night and I cry," Sergeant Iddles said.

Conviction premieres Tuesday 27th September at 8.30pm on ABC.

This post originally appeared on ABC News.

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