Police have issued more than 32,000 pre-charge warnings for petty crimes, resulting in a double-digit drop in charges before district courts.
Figures released under the Official Information Act reveal since pre-charge warnings came into effect on September 12, 2010, they have accounted for 10% of all charges.
During that period, 322,130 charges were laid by police nationally. Ten percent, or 32,931, were resolved using the warning facility.
The warnings are used when an offence justifies an arrest, and the offender has been taken to a police station for processing.
A sergeant or a higher-ranked officer could decide to release a person with a warning when the arrests met "evidential sufficiency requirements", Assistant Commissioner operations Nick Perry said.
The warnings were most commonly used to resolve public order offences. Disorder and breach of liquor ban offences account for half of all the pre-charge warnings issued.
They can only be issued to offenders aged 17 years or older and who have committed a low-level offence - maximum penalty of six months imprisonment or less. Methamphetamine and family violence offences, and admitted guilt, were excluded.
Asst Comm Perry said the warnings were counted in official police statistics. For the 2011-12 financial year, warnings resolved 21,811 charges, and reduced new charges to the District Court by 12%. Police also estimate the warnings saved just under 37,000 hours of front-line officer time - the equivalent of about 21 full-time equivalent jobs - each year, as police spent less time preparing files for court.
Acting Southern District Commander Inspector Lane Todd said in the district about half of all disorderly behaviour and breach of liquor ban offences were pre-charge warned.
The district was more conservative than other districts in its use of warnings with 10% of all charges being warnings. The national average was 12%.
Insp Todd said pre-charge warnings were proving to be an effective way of dealing with low-level offending, "with the offender being taken into custody and held for a period prior to release".
"A couple hours in a police cell can be quite a sobering experience and that is all that is required to ensure the offending stops."
Police Minister Anne Tolley said the focus of police was for officers to be in communities preventing and dealing with crime, and "less time doing admin in the office".