Police were very familiar with the person they were looking for, a 16-year-old boy who was allegedly plotting an Anzac Day massacre from his smartphone.

They had reportedly raided his home a year earlier and placed him in an intensive deradicalisation program after an Islamic State recruiter tried to involve him in another plot.

They also knew his 15-year-old friend, a Georges Hall boy charged last December over his alleged part in a plot to attack police and navy buildings.

He too had been raided a year earlier; he too had been diverted into a deradicalisation program.

However, both teens are now facing a maximum sentence of life in prison if convicted, raising serious questions over the multimillion-dollar deradicalisation efforts being led by the federal government and police.

"The government is certainly on the wrong track," government adviser and academic, Clarke Jones, who founded the Australian Intervention Support Hub, told Fairfax Media during the week. "[They] need to stop what they're doing, examine, reassess and scrap things that aren't working."

In an anonymous interview with The Australian last year, the Auburn boy's father had praised the government's $32.7 million National Disruption Group for bringing his son back from the brink.

Serious extremists are referred to the multi-agency taskforce and a suite of agencies, led by the police, come up with an individualised program.

The boy, who was reportedly skipping school and chatting online to extremists, was given a gym membership, started an electrician apprenticeship, started attending English-language sermons at a mosque with his father and had regular visits from police community contact workers, his father told the paper.

Fairfax Media has learned the 15-year-old was on a very similar program involving a gym membership, moderate sermons and support from a psychologist, a community sheikh and his school.

But the uncomfortable truth is that no one knows what works and what doesn't work when it comes to deradicalisation. There is no clear evidence base behind any solution and no way of evaluating them either, leaving us with a dangerous kind of trial and error.

"We don't even have a clear understanding of what we're trying to do," Anne Azza Aly, founder of People Against Violent Extremism and academic at Edith Cowan University, said. "Are we trying to stop an attack? Are we trying to stop someone from radicalising? Are we trying to just make someone comply with a program?"

Dr Aly, considered an international authority on this topic, has studied almost every deradicalisation program around the world. They range from Alcoholics Anonymous-style programs with close mentors to the Aarhus model in Denmark, which empowers the young person through social and family support.

She has previously urged the government to adopt Germany's Hayat program, a long-running approach first used on neo-Nazis that works on the idea that people cannot be deradicalised through force but rather by their friends and family.

The focus in Australia has largely been on broad, preventive programs that enhance social cohesion such as grants for sporting competitions and leadership seminars.

A study by the Australian National University and Global Terrorism Research Centre found only one program between 2010 and 2014, run in Victorian prisons, targeted radicalised individuals and efforts had "failed to reach those most in need of assistance".

The federal government says it has since changed its approach with a four-pronged strategy of prevention, early detection, challenging IS ideology or propaganda and intervention/rehabilitation.

Few details about the last prong, aimed at heavily radicalised people, are made public. More than 20 have gone through the National Disruption Group, all referred by police.

Psychiatrist Tanveer Ahmed was recently asked to assess a young man in prison over a brawl at Bankstown sparked by Sunni-Shiite differences. The man's lawyer had suggested a deradicalisation program and was directed to the Australian Multicultural Foundation, who aim to curb antisocial behaviours by training up the people who are closest to the subject.

Dr Ahmed had to press hard to find out what was available to the prisoner and how it might deradicalise him.

"It was all a bit vague," he said. "There was some involvement from a prison imam and a psychologist but one area we don't focus on is the family unit. Often a key contributor to radicalisation is the family."

Hass Dellal, executive director of the AMF, said their programs are intended to be preventive only. Following most lone-wolf terror attacks, families and friends say they knew that something odd was happening but didn't quite know what it was or what to do.

The AMF uses young mentors to train these people to recognise these warning signs.

"It's very hard to measure prevention, I'm the first to admit that," he said. "But we can't keep up with the uptake of our program. We've had young people at risk who have seen the light and are actually our mentors and trainers now."

Two things most experts seem to agree on is that deradicalisation needs to be community and family-led and it needs to be highly tailored to the individual, based on the diverse reasons behind their move into violent extremism.

Dr Jones' despair is directed mainly at the failure of government to build the crucial community relations. In many cases, relations have been broken due to successive policies perceived as anti-Muslim and "consultation fatigue" among community members who see the attempts to engage them as insincere.

The government needs to relinquish some control of programs but is finding it too hard and too risky to "let go," he said. "They want to continue bashing this square plug into a circular hole."

Aly said police are doing a great job but should not be at heart of the programs. "The source and the authenticity are really important. It's got to be led by someone who's got credibility."

Kuranda Seyit, secretary of the Islamic Council of Victoria, believes Australia is about "eight years behind the eight ball" and missed a golden opportunity to start researching deradicalisation during the Howard era and 2005 London bombings.

He recently helped coax a friend back from the Syrian border. The family were able to deradicalise him by totally removing him from his circle of friends in Sydney and relocating to a new environment in Melbourne. But he has watched many others slip through the net.

"Back then we had an opportunity to really do a lot of homework on this issue of radicalisation," he said. "Now we're facing the consequences of our apathy and dealing with a phenomenon we're not prepared to handle."