Alcohol-fuelled violence in New South Wales is at a decade low, but that may not remain the case under the new "one-punch laws" announced by Premier Barry O'Farrell, writes Greg Barns.

When it comes to criminal justice, politicians in Australia, almost without fail, think that locking people up and increasing police powers is a panacea.

New South Wales Premier Barry O'Farrell obviously subscribes to this view, manifested in his announcement of mandatory minimum jail terms for offences committed where alcohol and drug use is a factor.

Mr O'Farrell will find of course that his Government's strategy of filling the jails won't reduce alcohol- and drug-fuelled crime; in fact, it might even increase it, and it will lead to horrific cases of injustice.

So now a person who, when under the influence of drugs or alcohol, commits a serious assault, a wounding, an assault on a police officer in the execution of duty, an affray or a sexual assault, will go to prison for a minimum of between two and five years. If a person assaults another person and that person dies as a direct or indirect result, the mandatory minimum term is eight years.

The O'Farrell Government has cravenly fallen for the populist, media-driven campaign highlighting a couple of high-profile cases which peddles the lie that somehow alcohol- and drug-related crimes of violence in New South Wales are at epidemic proportions.

As The Guardian has pointed out, alcohol-driven violence in New South Wales "has been declining since 2008 and is the lowest since 2002, with 184.8 assaults per 100,000 people per year. It is however, still higher than the lowest point in 2000 of 136.6 assaults per 100,000."

What Mr O'Farrell's plans will do is risk increasing alcohol- and drug-related violence in New South Wales. That is what happens when you send people to jail.

Young people in particular - and it would be young males who will be incarcerated under these proposed mandatory minimum term laws more than any other cohort in the community - who enter the prison system tend to emerge with a greater disposition towards violence. This is inevitable because governments refuse to spend money on ensuring that prison is a humane and rehabilitative environment as it is in Scandinavian countries.

According to the 2013 Report on Government Services, released by the Productivity Commission, 42.5 per cent of New South Wales prisoners were re-offending within two years of release. Many of those reoffending are involved in crimes of violence.

There is also no evidence to suggest that putting offenders in prison for longer periods of time reduces crime. As Italian researchers Drago, Galbiati & Vertova found in a 2011 paper published in the American Law and Economics Review: "From a policy perspective, increasing prison severity does not seem an effective approach to reducing the post-release criminal activity of former inmates."

In fact, when it comes to young offenders, the immersion in the prison system leads to them having real difficulties re-integrating upon release. Because of the abject failure of governments around Australia to provide solid and sustained post release support for prisoners, the tendency to gravitate to networks created 'on the inside' is strong and this impacts on recidivism rates.

Finally, there is simply no evidence that increasing sentences or making them mandatory for particular offences stops would-be offenders. Such a view supposes that a would-be assailant fuelled by alcohol or drugs, or both, will weigh up the consequences of assaulting a person before committing the act. It is a theory built on a fairy tale view of how a person in such a situation will behave. In nine cases out of ten, there will be no such calm, rational approach taken.

The use of mandatory minimum terms is inherently problematic because it leads to gross injustices. In a liberal democratic society, individuals are entitled to have their case, with all its nuances and special features, examined by a court and have any sentence handed down tailored accordingly.

But under the O'Farrell Government laws, a person who is on the periphery of a brawl where alcohol or drugs are a factor would find themselves going to jail for at least four years if they are found guilty of affray. This is palpably unjust. As would be the case of a person who is provoked by a police officer's rough handling of them which causes them to lash out and assault the officer. Once again, that person would go to jail for at least two years.

And what about the person with serious drug or alcohol dependence who recklessly punches another person causing them harm? That person will be jailed for three or four years even though they need assistance, not punishment.

What Mr O'Farrell and his Government are doing is simply increasing the risk of filling jails with young offenders and other offenders. They are creating the conditions for a more violent New South Wales in the future: a New South Wales in which there are hundreds if not thousands of embittered ex-prisoners released back into the community with nothing having been done to address

the cause of violent offending - addiction, mental illness or behavioural problems.

Greg Barns is a barrister and spokesman for the Australian Lawyers Alliance. View his full profile here.