Aims Each year around 37 children in the US alone are killed by heatstroke through being left unattended in vehicles. In the past, caregivers of these children have been charged with neglect or manslaughter. In recent cases such as Noah Zunde (2017), inquests have drawn on expert witnesses who have expanded on a psychological basis for these cases, pointing at an ‘overriding’ habitual memory i.e. the routine of taking a child to playgroup. The term ‘forgotten baby syndrome’ has come to prominence to describe a scenario whereby a child comes to injury by being unintentionally left in a car. The implication being that a parent could be acquitted of manslaughter if the child was truly forgotten. This may have far reaching consequences for defining neglect. We completed a literature review to assess the proportion of unintentional vs intentional cases where a child was injured by heatstroke by being left unattended in a vehicle.

Methods A systematic review of the literature was completed on Medline. In addition data was taken from the US national safety council via noheatstroke.org.

Results The USA national safety council reviewed 743 child deaths from heatstroke after being left unattended in a vehicle from 1998–2017 in 54% the child was unintentionally left, 27% the child gained access to the vehicle, 18% the child was intentionally left and 1% circumstances were unknown. A Brazilian study (Costa 2016) identified 31 cases (20 fatal) in which 71% were unintentional, 3% child gained access, 23% were intentional and 3% unknown. A small Italian study (Ferrara 2013) identified 16 cases (2 fatalities) of which 18% were unintentional, 75% were intentional and 6% unknown.

Conclusion Most children who die through being left unattended are reported to have been left in vehicles unintentionally. Further research is required to establish what initiatives work, if most cases are truly unintentional, public health strategies that merely explain the dangers of leaving a child unattended such as the American, ‘It Can Happen’ are less likely to be successful – parents may be aware of the danger, but simply forget the child is in the vehicle. Future interventions that are universal such ‘child reminder systems’ in cars may be more successful. The difference between ‘forgotten baby syndrome’ and neglect remains difficult to define.