Unprotected by insurance... trees at the National Arboretum.

Unprotected by insurance... trees at the National Arboretum. Photo: Rohan Thomson

ACT police have recorded the country's lowest 30-day clearance rates for investigations into armed and unarmed robberies, sexual assaults, motor vehicle thefts and unlawful entry, according to new data on government services.

But Canberrans have demonstrated faith in their police service.

ACT officers recorded the best results for professionalism, honesty, fairness and equality in the nation.

The Productivity Commission released its Report on Government Services 2013 on Thursday.

The report shows poor results for the finalisation of investigations within 30 days in the ACT during 2011, based on Australian Bureau of Statistics data.

But it does urge ''extreme caution'' in comparing clearance rate figures across jurisdictions, saying different business rules, procedures, systems, policies, and recording practices between various police agencies may warp the data.

ACT police recorded the lowest figures for finalising investigations within 30 days for a number of property crime types.

Just 5.4 per cent of motor vehicle theft investigations were finalised within 30 days, well below the national average of 14.1 per cent.

Just over 3 per cent of investigations into unlawful entry with intent were finalised within that timeframe.

This is compared to the national average of 10.1 per cent.

The finalisation rates of investigations into sexual assault, armed robbery, and unarmed robbery were also the lowest in the country.

The ACT recorded exceptional results in a 2011-12 survey on community satisfaction with policing, performed by the Australia New Zealand Policing Advisory Agency.

The territory's police received the most positive responses for a number of statements put to respondents, including ''police perform job professionally'', ''police treat people fairly and equally'', and ''police are honest''.