It is estimated that 7% of the prison population in the UK has a learning disability,compared to around 2.2% of the general population. A study by Prison Reform Trust in 2008 found that people with learning disabilities are seven times more likely to reach into contact with the police, five times more likely to be subject to control and restraint, or three times more likely to suffer from anxiety or depression,and spend time in solitary confinement.
These numbers are estimates rather than straight statistics because there is no system in status to screen, identify, or record whether a prisoner has a learning disability. In a research paper from 2005,psychologist John Rack estimated that around 20% of prisoners have some form of “hidden disability” which affects their performance in education and work settings. It's worryingly disproportionate, and it begs the question - whether prisons don’t have systems in status to even identify these people, or how can they begin to give them the support they need to survive in a prison environment?
Source: bjp-online.com