The way suspects are held on remand in jail should be overhauled to ensure expensive prison places are not being wasted, according to the Chief Inspector of Prisons.
Nick Hardwick says remand prisoners receive less support than convicted criminals, have an increased suicide risk and poorer access to services.
On average, prison places cost £40,000 a year with between 12,000 and 13,000 remand prisoners held for an average of nine weeks.
Mr Hardwick said: "Far from being treated more favourably, this thematic review has shown that they (remand prisoners) all too often receive less support and help than convicted and sentenced prisoners."
The report, based on inspections at 33 local prisons, focus groups and fieldwork in five jails found prison rules and what actually happened rarely matched up.
Michael Spurr, chief executive of the National Offender Management Service (Noms), said: "This report has raised some important issues which Noms is addressing."