"Public agreement that speed limits are appropriate is central to achieving good levels of compliance, which is needed to maximise safety benefits," AA Otago chairman Malcolm Budd said.
"If a speed limit feels unreasonably slow to people, then it is very difficult to get the majority of people to comply."
The city council has proposed widespread reductions in traffic speed limits in and near Dunedin, including a series of 30kmh limits in residential areas and 60kmh limits in much of its rural roading network.
More than 1500 public submissions were received on the proposal and a hearing starts today.
Mr Budd said the council should undertake further work to understand community sentiment.
"Reductions in speed limits have consistently been proven to result in reductions in trauma from crashes, and can be a relatively cheap and easy way to bring down harm on the roads," he said.
"At the same time, we firmly believe that speed limits — like all rules — need to have the endorsement of the public."
The AA was comfortable with lower speed limits around schools.
"As a general principle, we feel variable speed limits around schools are most appropriate, as this approach ensures lower speed limits are in place when children are travelling to and from school and there are greater levels of activity on the road and roadside, including children, and therefore a higher degree of risk."
Disabled Persons Assembly regional policy adviser Chris Ford said existing 50kmh limits were too high for many roads.
"We agree that redesigning the road network to include more traffic-calming measures and urban amenity upgrades will assist the process of enabling lower traffic speeds to be introduced into more areas in the future," Mr Ford said.
He noted the council was not due to adjust speed limits in Mosgiel before 2027 and felt it should happen sooner.
Dr Benjamin Nuttall, of Dunedin, supported 30kmh zones and agreed with proposed changes to rural speed limits.
"I work as a doctor and regularly see death and serious disability from road traffic accidents — most involve excess speed."
