A study of inmates at Christchurch women's prison found nearly every woman interviewed had a history of multiple traumatic brain injuries.
The study was cited by Dr Ian Lambie, the chief science advisor to the justice sector, who has published a discussion paper looking at the prevalence of head injuries in people who end up in courts and prisons.
People with brain injuries are over-represented in the justice system, and Doctor Lambie says more could be done to deal with the problem.
Ben Strang reports.
