Nick Hardwick said it was not fair that these people were being treated less well than convicted prisoners, and that they should not be housed with them.
He said that those on remand get fewer rights because they’re in a position of flux, and they don’t get things like letters and visits, which convicted prisoners would expect.
Speaking to BBC Radio 4’s Today show, he said the reasons for this were as follows: "One is because I think often prison officers don't know the rules that apply to remand prisoners. And secondly, they simply get muddled up in the general population, so even if prison officers do know the rules, they sometimes don't know who the remand prisoners are."
"There are some costs involved, but fundamentally this is an organisational issue... We want [prisons] to organise the system differently so remand prisoners can be distinguished and so people know who they are and make sure they get what they are entitled to."
He added that he thinks that this is no longer seen as an issue because it has slipped off the agenda.
Mr Hardwick investigated 33 prisons when putting together the report, using the 1999 Prison Rules as a guideline. This sets out specific legal entitlements for those on remand, including an obligation to give each person their own cell. However, the report found that governors had personal discretion, and cell sharing was a regular occurrence.
The prison service said it was busy addressing the issues raised in Mr Hardwick’s report.