The prioritisation of high risk offenders through risk assessments and police oversight through sex offender registration aim to bring about the effect of preventing reoffending in various ways. Routine Activity Theory states that three factors are required for a crime to occur: a motivated offender; an available victim; and absence of a guardian. Guardianship is therefore considered a critical feature of crime reduction, thereby contributing to successful community reintegration and rehabilitation, and is a key feature of situational crime prevention (Peled-Laskov and Gimshi, 2014). Guardianship (e.g., through offender registration) works to reduce offending by increasing effort and risks of apprehension, reducing rewards associated with offending, reducing access to potential victims (opportunities) and reducing excuses and justifications (Cornish and Clarke, 2003). Deterrence is the fear of receiving certain, swift and proportionate punishment (Akers et al., 2017) which reduces offender motivation to offend, and is closely linked to effort, risk, reward, and opportunity elements of guardianship. Disruption occurs when opportunities to offend are avoided or reduced, similarly reflecting effort, risks, rewards, and access elements of guardianship. Deterrence and disruption can further lead to an ongoing reduction in motivation to offend through processes of social learning (Akers et al., 2017), reducing overall risk.
Police oversight delivers formal guardianship as convicted child sex offenders are required by law to regularly report their residential and work addresses and other contact details to police (Day, 2014; Powell et al., 2014; Sandler et al., 2008). Police awareness of residential composition, work locations, and use of offender contact details is thought to facilitate risk assessment and management to minimise opportunities to offend and enhance offender perceptions of guardianship. Through police oversight, registration schemes attempt to control known sex offender behaviour in the community. The idea here is that through enhanced guardianship, the mere availability and monitoring by police can deter offenders from participating in criminal behaviour (Hollis-Peel et al., 2011). Such oversight works by creating a sense of certain, swift and proportionate punishment within the offender, deterring them from offending despite opportunities to do so. In addition to registration motivating known offenders to not reoffend via principles of specific deterrence, it acts as a general deterrent for potential offenders due to awareness of the ongoing burden of registration schemes for child sexual offenders (Drake and Aos, 2009).