The main aim of this study was to examine the effect of a potential guardian on the severity of child sexual abuse. Using data obtained on crime events from adult child sexual offenders incarcerated in Queensland (Australia), mixed-effects logistic regression analyses were conducted to examine the effect of potential guardianship on the severity of abuse. Controlling for victim and situational characteristics, the analyses showed that the presence of a potential guardian reduced the duration of sexual contact and the occurrence of penetration. Presence of a potential guardian decreased the risk of sexual penetration by 86%. The study highlights the importance of the presence of a potential guardian for reducing the severity of child sexual abuse, and suggests more broadly that guardianship may be an important protective factor in sexual offending.