There have been well-documented misunderstandings about the use and powers of section 5(2) of the Mental Health Act (MHA) 1983, however there are no published studies looking at how education of the clinicians involved affects any outcome measures. The aim of this study was to examine the impact of training junior doctors in the correct use and powers of section 5(2) of the MHA 1983. Data was collected before and after teaching junior doctors in Nottingham. There were proportionally fewer section 5(2)s MHA 1983 implemented by junior doctors after the teaching. A suggested gold standard for reclassification rates was found and trends in better practice are also reported. Teaching junior doctors about section 5(2) MHA 1983 increases the proportion of senior doctors implementing the section and this should improve patient care. All junior doctors should receive specific teaching about section 5(2) at the start of their training.