A man who sustained a serious head injury when he was attacked with a pole and subsequently arrested and held in custody for ten hours is suing the police.
Dean Hutton, from South Yorkshire, was left without medical treatment despite the force knowing the nature of his injury, lawyers Irwin Mitchell said.
South Yorkshire Police said it accepted liability for the injuries.
Its solicitors are consulting with Mr Hutton's legal team, the force said.
Mr Hutton, 26, from Wath-Upon-Dearne, was arrested after the fight in 2009 because he had failed to appear at court on a previous charge.
Paramedics recommended he be taken to hospital because of the blow to the head but Mr Hutton declined the advice, a report found.
'Struggling to breathe'
Stacy Clements, a lawyer at Irwin Mitchell, said: "Had the police taken note of the fact that Mr Hutton had suffered a head injury and consequently recognised the symptoms he showed through the night, he would have received medical attention much sooner.
"It was only 10 hours later, when he was struggling to breathe and had blood around his mouth that officers acted, rushing him to Rotherham District General hospital."
Mr Hutton was then transferred to Royal Hallamshire Hospital in Sheffield for emergency surgery but suffered a serious brain injury.
Roy Hutton, Dean's father, said: "Before his brain injury, Dean was completely independent but now needs help with almost everything he does.
"But Dean is battling back bravely and his rehabilitation has helped him come a long way."
South Yorkshire Police said: "Our thoughts remain with Mr Hutton, his family and friends."
A spokesman for Irwin Mitchell said: "We are now working to secure a full settlement to ensure it can provide for Dean's lifetime needs."
An Independent Police Complaints Commission investigation in 2010 concluded errors were made by South Yorkshire Police officers when dealing with Mr Hutton.
The IPCC investigation said the custody sergeant was aware that Mr Hutton had received a head injury but no record was made.
Instead Mr Hutton was classified as drunk and placed on half-hourly checks.
The investigation concluded the failure to record the details of the head injury when Mr Hutton entered custody meant opportunities were missed to recognise the seriousness of his injuries.