Two prisoners occupy a cell intended for one. How many are living in 'crowded accommodation'?
The answer, unsurprisingly, is two. Except last week the Ministry of Justice (MoJ) revealed that in some cases only one prisoner would have been counted in such a situation, based on a misunderstanding in some prisons that they were only counting prisoners 'in excess' of the designed capacity.
The knock-on effect is that since 2008, the National Offender Management Service has been undercounting prisoners living in crowded accommodation. So the most recent published figures are now wrong.
Last year we factchecked how many prisoners in England and Wales were living in overcrowded accommodation. We've now updated our figures to match the latest revisions provided by the MoJ.