The way an open prison oversees the release of high-risk prisoners shows "serious concerns", a report has found.
About two thirds of inmates at HMP Leyhill, South Gloucestershire, are deemed as high-risk and about 65% have been convicted of a sexual offence.
HM Inspectorate of Prisons found the planning and management of public protection arrangements "was not sufficiently robust".
More than half of last year's parole board hearings were deferred, it added.
The report, from inspections carried out in February and March, said one disabled prisoner was still at the prison despite being given a release approval date more than a year before.
Other prisoners were being transferred to the prison "just weeks" before their release, with probation staff working "predominantly off-site" for the past year, it added.
"Poor management oversight of public protection arrangements for those prisoners approaching release was a serious concern," the report said.
"The planning was not sufficiently robust or timely, particularly for those convicted of sexual offences."
'Fear of repercussions'
Of the black, Asian and minority ethnic prisoners held at the site, almost two thirds said they felt "bullied or victimised" by prison officers and "were afraid to speak up for fear of repercussions".
The report found relationships between staff and inmates needed to improve "so that all prisoners are treated with respect".
However, inspectors also found prison staff had "worked well" to control an outbreak of Covid-19 at the site in October.
Two staff and five prisoners, who were found to have the virus on arrival at HMP Leyhill, were "effectively isolated", the report said.
It was also "positive" that "most prisoners" able to work were employed, the report found.
About 500 men are held at the prison, near Wotton-under-Edge.