Three days after Angela Williams was hit by a postie bike, she was sent to prison for a crime she'd committed 13 years earlier — one she thought she'd already served time for.

She had spent the years in between getting her life back on track: kicking a heroin addiction, starting a creative arts degree and getting her son out of foster care.

"In 2009, when I submitted my honours thesis, I felt like I was in control of my life," she says.

"I had a path towards the future."

But her past was about to catch up with her.

The original sentence

Ms Williams was first sentenced in October 1996, when she was 19.

After breaking into a house in search of a drug stash with three men, including her then boyfriend, she was sentenced to 15 months' periodic detention.

After five months of "weekends" at Emu Plains Correctional Centre, west of Sydney, she signed up for a 12-month rehab program.

She also stopped attending her weekly detentions.

At the time she was re-arrested Ms Williams had completed an honours degree and was raising her son. ( Supplied )

Ms Williams says she knew she had time left to serve, so three months into her rehab, she decided to turn herself in and complete her weekend detention.

But she claims that when she did, a police officer told her that her sentence had been commuted, and if she kept up with the rehab program, she could consider her sentence served.

So, despite having 10 months and one day left on her original sentence, when she finished rehab, Ms Williams thought she'd done her time.

But that wasn't the case.

In February 2010, she was hit by a postie bike. When she gave a statement to police, she learned there was a warrant for "incomplete periodic detention".

Completing rehab does not negate the need to also complete detention.

By law, Ms Williams was required to serve out the remainder of her original sentence in full-time custody.

ABC RN contacted Corrective Services NSW, but they were unable to comment on her case.

Maximum security and the realities of home detention

Following her arrest in 2010, Ms Williams spent 45 days at Mulawa (now Silverwater Women's), a maximum-security jail, and Berrima Correctional Centre.

Then she was moved to home detention.

"When I was in prison, all I wanted to do was get home to my house, and my son, and my family. And from that angle on home detention, it makes it feel preferable," she says.

Ms Williams did get to live with her son, sleep in her own bed and eat her own food, but her old life, which she thought she'd moved on from, infiltrated the walls of her new one.

She had to wear an electronic monitoring device.

Apart from pre-approved activities, which included work in a call centre and a fortnightly grocery shop, she wasn't allowed to leave her house unless she had gained written approval two weeks in advance.

Ms Williams served eight-and-a-half months under home detention, and says in many ways it was lonelier than prison.

"When you're in prison, at least there's people around you, other inmates who know what's happening," she says.

There was little accountability or support, and the academic and community ties she'd worked hard to cultivate broke down.

"I really didn't do much socialising. I was very ashamed to be in the situation, and very angry," she says.

Justice served?

Ten years on, Ms Williams, who has written about her experiences in a memoir titled Snakes and Ladders, says the decision to put her back in prison after she'd got her life back on track shows rehabilitation doesn't count for much.

"I did rehabilitate, and they put me back in there anyway," she says.

"It didn't matter that I spent 13 years not committing a crime, it didn't matter that I'd given up drugs, gone to university, none of that mattered.

"We put people in prison too quickly, and too easily."

After her home detention, Ms Williams says she had to try to re-establish "the aura of responsible parent". ( Supplied )

Rehabilitation is only one purpose of sentencing; the Judicial Commission of NSW also highlights the importance of retribution or "adequate punishment".

The State Parole Authority of NSW told ABC RN it does not comment on sentencing options or their benefits.

However, a spokesperson said: "The request for [Ms Williams] to be assessed for home detention was approved which then allowed her to be released on a temporary release order. In doing so, it was the quickest way to have her out of custody while her matter was being reviewed by the parole board."

The increasing use of home detention and electronic monitoring

When Ms Williams went back to prison in 2010, she knew how the system worked, because she'd been there before.

But she was caught off guard by how hard home detention was.

Data from the Australian Bureau of Statistics shows community-based orders, including home detention, are on the rise.

This is despite the number of male prisoners in Australia holding steady, and the number of female prisoners in Australia decreasing for the first time in almost a decade.

Marietta Martinovic, an expert in home detention from RMIT University, says electronic monitoring specifically has increased by 150 per cent over the past three years.

She puts this down to state governments' increased spending, coupled with sentencing reforms, which have made it easier for courts to add electronic monitoring sanctions to various types of orders.

Dr Martinovic says the use of electronic monitoring has increased by 150 per cent in three years. ( Supplied )

She also says a lot has changed since 2010, when Ms Williams did her time.

The switch from radio frequency-based technology to GPS trackers is one of the biggest changes.

"GPS technology allows the authorities to know where people are at any one time, so people are rarely detained to their homes these days," she says.

While exclusion zones still apply for sex offenders or violent offenders out on parole, people are mostly able to "roam around free".

"The impact of wearing the device has changed remarkably, because of the technology that is applied," Dr Martinovic says.

Dr Martinovic says although there is still shame associated with wearing a monitoring device, home detention is preferable to incarceration, especially for women.

She says community-based orders can help them keep ties with their family, and with their communities.

"They are able to keep their community ties. However weak they may be, they're still able to keep them," she says.

But Ms Williams, who a decade on is getting her life back on track for the second time, found maintaining a relationship with her son was complicated, especially regarding "parental authority".

"Home detention was an emergency dressing on a wound to our relationship that could have been avoided," she says.

"As much as home detention prevented cracks getting wider, from the second those cops said they had to arrest me the damage had started."

'In and out until they die'

For Dr Martinovic, home detention might be part of the solution to one of the biggest problems facing the justice system — recidivism.

She says no matter which Australian jurisdiction you look at, the likelihood of reoffending drops by about half when people serve community-based orders — from 45 per cent within two years for people coming out of prison, to between 10 and 20 per cent.

Committing another offence wasn't what landed Ms Williams back in prison, but the cycle of reoffending is something she's all too familiar with.

"Too many of the people that I met in 1996 and 2010 are silenced by the system. They're just invisible little numbers that keep rolling around again and again and again and will go in and out and in and out until they die," she says.

"I'm telling this story for those people who can't ever tell the story."