Latest crime statistics show Canterbury had the country's biggest decrease in crime, but it also had a jump in sexual assaults and the severity of family violence.
Overall crime in Canterbury fell to the lowest level in 16 years, including car thefts, property damage, and robberies each dropping by more than 20%.
Acting District Commander John Price says the flow-on effects of the earthquakes are the major factor, with a big increase in police numbers, the closure of the central city and closer ties within the community.
But there was also a 24% increase in sexual assaults, many of which happen in the home.
While family violence numbers have dropped slightly, police are concerned at the increased severity in attacks.