Compensation payments to prisoners in England and Wales almost doubled last year to more than £3 million, official figures revealed today.
The figure includes £1.6 million paid out in 12 cases of medical negligence which were settled in 2009/10 and more than £530,000 paid to victims of assaults by prison staff.
In 2008/09 a total of £1,669,312 was paid out but in 2009/10 payments totalled £3,286,521.
Figures released by the Ministry of Justice in response to a Freedom of Information request by the Press Association show that last year:
* £1,609,250 was paid out in medical negligence cases;
* £534,628 was paid out in compensation for assaults by staff;
* £259,943 was paid out for unlawful detention.
The figures reveal that in the last five years £13,069,631 was paid out in compensation to prisoners.
The highest single payout since 2005/06 was £2.8 million for a personal injury claim, with the second biggest payment £1.14 million for medical negligence.
Compensation paid out for assaults by staff tripled last year to £512,225 from £165,950 in 2008/09, the figures showed.
The number of settlements over assaults by staff also increased to 19 in 2009/10, more than at any time in the past five years, the figures showed.
There were just seven such settlements in 2008/09, nine in 2007/08, 10 in 2006/07 and five in 2005/06.
The Ministry of Justice also lost two court cases over assaults by staff in 2009/10 and was ordered to pay out a further £22,403.
The figures also showed settlements totalling £107,057 were made in relation to 13 assaults by prisoners in 2009/10, compared with 16 settlements for £79,819 in 2008/09 and eight settlements for a total of £39,433 in 2007/08.
Of the 10 highest payments made since 2005/06, four totalling almost £4 million were for personal injury and six, totalling £2.4 million, were for medical negligence.
In 2009/10, the Ministry of Justice settled 322 claims, fewer than the 409 settled in 2008/2009, but paid out almost double.
The department also lost 11 court cases in 2009/10 and was ordered by courts to award £28,629.
A Ministry of Justice spokesman said: "Like all citizens it is open to prisoners, staff and third parties to pursue civil litigation claims for any perceived wrongdoing.
"Each litigation case is dealt with on its merits and, so far as the evidence allows, all claims are robustly defended. In fact the Prison Service defends significantly more civil claims than are settled.
"Such claims are only settled on the basis of strong legal advice. The amount of compensation is determined following a full analysis of all the available evidence and taking account of the Judicial Studies Board Guidelines.
"Taking indefensible cases through to court only results in more expense to the public purse.
"Prisoners may also seek compensation through the internal complaints procedures, without going through the legal process, for items such as lost/damage property.
"Each claim is investigated and if substantiated and the prison found to be at fault for the loss/damage, the prisoner may receive compensation."
Taxpayers' Alliance campaign manager Emma Boon said: "Prisoners are already detained at great expense to law-abiding taxpayers.
"It is a disgrace that criminals are able to claim so much cash from compensation claims, especially at a time when budgets are already stretched.
"Sadly there is a compensation culture these days, but instances of prison officers assaulting inmates cannot be tolerated and the Ministry of Justice and prison staff need to do all that they can to keep these compensation payments to a minimum, and protect taxpayers' money from unnecessary claims."
The £2.8 million settlement, the largest compensation payout by the Prison Service, was made in 2005-06.
At the time, the Government would not comment on reports that the out-of-court settlement was made to an inmate who required long-term medical care because of self-harm committed in jail.
The second biggest payout, £1.14 million, went to former prisoner Gregg Marston, of Shoeburyness, Essex, who was left crippled when a doctor failed to send him for an urgent examination.
His case, which was settled out of court, centred on his treatment at Chelmsford jail in Essex in February 2000.
He was taken there after failing to appear at court for driving offences committed in breach of the terms of his release from a four-year sentence for burglary.
Marston complained of back pain when he arrived at the jail but was not referred to hospital until the next day.
As part of his legal action, a consultant in spinal injuries told the Prison Service that, if Marston had been referred a day earlier, he might have undergone surgery to save the use of his legs, according to reports.
Figures released in June 2007 showed the third biggest in the last five years, £575,000, went to a male prisoner in Northallerton young offenders' institution, North Yorkshire, who had apparently attempted suicide, while Wormwood Scrubs settled another claim for £472,000 - the fourth biggest payout in the last five years.
Reasons for these two payments were not revealed but were included in the category of injury claims for official misconduct and human rights' breaches.Reuse content