A prisoner who was on a no-wash protest was not offered a shower before attending a court date, the Northern Ireland Prisoner Ombudsman was told.
A number of dissident republicans imprisoned at Maghaberry Prison in Co Antrim are involved in the protest in which they smear excrement over their cells.
The action, which started in May 2012, was in opposition to strip searches.
Previously republicans, including the Provisional IRA and INLA, engaged in years of no-wash protests for political status at the Maze Prison, which culminated in the hunger strikes of 1981 during which 10 men died.
The Prisoner Ombudsman for Northern Ireland revealed that within the last year, a prisoner who was engaged in a protest at Maghaberry Prison was not offered a shower before going to court.
It was one of a number of complaints detailed in the ombudsman's annual report for 2017-18.
The report said 'Mr F' complained about not being offered a shower – while he was on dirty protest – before going to court from Maghaberry.
As a result the Ombudsman recommended that the Northern Ireland Prison Service's dirty protest and faecal contamination policy should be updated to provide that prisoners engaged in the protest should be offered a shower before a court appearance, or any activity outside the prison.
Among the 1,953 complaints received by the Prisoner Ombudsman in 2017-18, all but 167 of these complaints were from separated prisoners on Roe 3 and 4 landings at Maghaberry.
Inmates can ask to go into separated wings if they feel they are political prisoners and are associated with paramilitary groups.
Complaints received from prisoners in Northern Ireland last year ranged from the availability of art supplies, late newspapers and alleged assaults.
One prisoner said a prison officer had "deliberately sprayed him with air freshener", a complaint which was upheld.
Another complained on three occasions his newspaper had arrived a day late.
"The investigation established this was true and that a daily paper was the service Mr H had paid for," the report found.
The prison service said the delays were due to staff shortages.
The ombudsman's report said it considered the matter "unacceptable", and recommended that the prison service prioritise the delivery of newspapers to ensure that those who pay for the service receive their papers daily.
However, the prison service did not accept the recommendation, pointing out staff pressures, and adding that all prisoners have access to television and radio.
"So there is no impediment to keeping up with current affairs," the ombudsman report recorded the response of the prison service as.