Prisoners in Northern Ireland have received compensation payouts adding up to more than £700,000 over the last five years.
Figures obtained by the Belfast Telegraph reveal there were more than 1,800 injury claims, resulting in payments of £696,348.
Since 2013 some 160 claims for lost or damaged property have been lodged, leading to payouts totalling £19,148.
It already costs £53,408 per year to keep someone locked up - more than double the average salary in Northern Ireland.
Statistics released under Freedom of Information show a sharp rise in claims put forward at Magilligan Prison near Limavady, a medium to low security facility for male prisoners with less than six years on their sentence.
It currently has 425 inmates and a capacity of 570, but in 2016 there were 690 injury claims costing the taxpayer £196,255 in compensation payments.
This was almost 10 times the amount that had been paid out the year before - in 2015 there were only 99 injury claims and £19,900 paid out.
The claims include assaults by prisoners and staff, trips and falls, smoke inhalation and unsafe working facilities.
The steep rise in figures is driven by mass claims from prisoners that their human rights have been breached in Magilligan.
In 2013 and 2014 there were fewer than 10 'breaches of human rights' claims, and a rise to 62 in 2015, but 2016 saw this figure rise to 638, an increase of 929%.
It is thought that some of these may be historical claims from former prisoners who have taken action after their release.
The Northern Ireland Prison Service has said that 90% of these claims relate to the sanitation at Magilligan, where prisoners have been slopping out, meaning that they have been forced to use chamber pots instead of functioning toilets if a member of staff is not present to take them to use the facilities.
TUV leader Jim Allister expressed concern at the compensation payments.
"It's not just the £700,000, because all of those claims will be legally aided and it will be a much higher figure than what these show," he said.
"I think the fault lies with the legal aid situation and prisoners are given unquestioning legal aid, making it easier for them, meaning that the balance is in the favour of the prisoners, as it is cheaper for the State to pay for them instead of paying for the legal and court costs."
The Prison Service said: "The Prison Service receives various claims for compensation from prisoners.
"Each claim is dealt with individually and resolved appropriately.
"Claims in recent years by prisoners in Magilligan have largely been due to unsatisfactory sanitation in a number of accommodation areas of the prison.
"However, this accommodation is being upgraded to ensure it meets with the required standards.
"While compensation payments do place pressures on financial resources, every effort is made to address issues in a way which negates future claims."
Out of the three prisons in Northern Ireland, Hydebank Wood, which accommodates young offenders and female offenders, had the smallest amount of claims over the five years.
A total of £30,250 was awarded in compensation.