Late last year Porter said the Government did not support justice reinvestment because it would lead to either softer sentences or the greater use of parole: "We see imprisonment as an indispensable and necessary part of the justice system."
But after the Banksia Hill row the mood has shifted. Corrective Services Minister Joe Francis has indicated the Government is now prepared to use data identifying local government areas with high rates of imprisonment. The move has immediate implications for indigenous offenders.
The rate of indigenous jailing in WA has almost doubled in the past two decades, with Bureau of Statistics figures showing the state exceeds a national rate that is 14 times higher than for other Australians.
In WA Aborigines are jailed at a rate 18 times higher than other non-indigenous offenders. Almost three-quarters of youths in custody are indigenous.
Aborigines are also more likely to reoffend. In WA, 70 per cent of male adult indigenous prisoners, and 80 per cent of male juveniles, are repeat offenders.
Deaths in detention also remain a major concern. In WA 40 per cent of all deaths in custody are indigenous.
The underlying causes are well documented: endemic problems of health and disease, poverty, unemployment, overcrowded housing and homelessness, and high rates of alcohol and drug abuse.
But while large-scale state and federal programmes are in place to attack severe disadvantage across almost every measure of well-being, there is growing support for cross-matching data for new systems of justice reinvestment.
Faced with widespread flaws in the criminal justice system and crowded jails that in Australia cost about A$3 billion ($3.6 billion) a year, acceptance of the concept is growing.
A Senate committee is at present inquiring into justice reinvestment, focusing on the drivers behind 30 years of growth in the nation's imprisonment rate, the economic and social costs, the over-representation of disadvantaged groups including Aborigines and Torres Strait Islanders, and the cost, availability and effectiveness of alternatives to imprisonment.
The inquiry also embraces the collection of data, and the effectiveness of justice reinvestment in other countries.
The key is matching social and economic data with crime and imprisonment rates, in effect identifying suburbs and postcodes with crime blackspots.
The data covers areas such as education, unemployment and social disadvantage.
Studies and overseas programmes have confirmed significant correlations between disadvantage and imprisonment, especially in remote areas of Australia where the delivery of goods and services is expensive.
The aim of justice reinvestment is to target money and specific social programmes for these areas with the intent of raising living standards and conditions, and providing alternatives to crime.
WA's apparent move towards using recent data identifying the areas where crime and imprisonment rates are at their highest has been welcomed by Aboriginal and Torres Strait Islander Social Justice Commissioner Mick Gooda.
"Adopting an approach that shifts money from the prison system to those communities with high crime rates in a bid to address the underlying causes of crime, such as drug and alcohol dependency, unemployment and poor educational opportunities, not only makes sound fiscal sense but makes logical sense," he said.
"And no group is possibly in greater need of a shift in criminal justice strategies than Aboriginal and Torres Strait Islander peoples who continue to be incarcerated at alarmingly high rates in WA and right around the country."