Peninsula Community Legal Centre, which has a branch in Cranbourne, has lent its voice to a "Smart Justice" coalition

calling for sentences that are "effective and human-rights compliant".

The legal centre is against mandatory minimum jail terms, including for offenders aged 16 and 17, because it disallows decision-makers from taking into account individual circumstances.

Acting principal lawyer Brendan Stackpole admitted the "tough on crime" approach seemed popular but was confident that if the public was well-informed it would support the campaign.

He said surveys showed that when people have the same information as given to a court, they tended to impose the same or a more lenient sentence than the court.

"Whilst imprisonment is appropriate in some cases, research shows that imprisonment has no positive effect on re-offending rates and often results in higher rates of re-offending."

The push for heavier sentences stemmed from the popular idea that crime was increasing and more violent, he said. This was largely because of a focus on crime and sentencing in the media, he said.

"In fact, crime in Victoria has consistently dropped over the past nine years - by about 30 per cent per head of population," he said.

Recent police statistics in Casey-Cardinia support and contradict the statewide trend.

In Casey, crimes against the person went up 5.4 per cent in the 2010-11 financial year, with police particularly concerned by alcohol-fuelled violence.

In Cardinia, crimes against the person dropped by 28.6 per cent.

Last July, the state government launched an online public survey on sentencing, MyViews. The results are yet to be released.