A young woman repeatedly punched by a policeman is demanding an apology and compensation.
CCTV pictures show 20-year-old Toni Comer being hit five times by PC Anthony Mulhall.
The officer, who has been suspended from frontline duties, says he was trying to deaden her arm so she could be restrained with handcuffs.
The mother-of-one said: "I thought police arrested people for doing things like that, not that they did it themselves.
"Afterwards, there were bruises on the back of my neck, the side of my head and on my arms."
She added: "I would like to see some kind of justice so this never happens to anybody else in the future.
"He should pay some compensation for what he did to me."
She is taking civil action against the officer.
Ms Comer - who suffers from epilepsy - had been thrown out of the Niche nightclub in Sheffield. Police were called when she vandalised a car.
She admits drinking brandy and cokes before arriving at the club, but says her mind went blank after entering and she has no recollection of what followed.
PC Mulhall said he had been kicked and spat at by Ms Comer, who had also tried to bite him.
In a statement he said he tried to subdue her to no avail: "There was no visible effect and in the end I had to use brute force and both hands to bend her arm at the elbow to place her wrist in the cuff."
He said he hit her "as hard as I was physically able" to deaden her arm so she could be restrained.
She was put in cuffs and dragged away with her trousers down as a police dog handler watched.
Ms Comer has pleaded guilty to criminal damage and was given a conditional discharge and ordered to pay £250 compensation.
Ms Comer's parents, Leroy Walcott and Lisa Comer, said their daughter had a fit in the club.
Mr Walcott, told Sky News: "What kind of an example does this set? My daughter is 5ft 6ins and weighs nine stone and I'm sure two police officers could have restrained her. It's just not acceptable."
Ms Comer said her epilepsy started when she was 17 and pregnant with her three-year-old son Tyrees. She doesn't take medication because of possible side effects if she wants more children.
She added: "I'd like to see an apology and for the police to be aware that these type of illnesses are around, because it can be mistaken for being drunk."
The Independent Police Complaints Commission has launched an investigation into the allegations.
IPCC Commissioner Nicholas Long said: "I have seen the CCTV footage and decided it is in the public interest for a wholly independent investigation to be conducted."
South Yorkshire Police Chief Constable Meredydd Hughes told Sky News he'd been horrified when he first saw the CCTV clip. However, he added he had now seen the whole footage and there was more to the case than first met the eye.
Lord whatever happened to trying to be decent and hardworking, now we are having epilepsy used as an excuse for being a drunken scally oik. I wouldn't blame the copper if he had hit her, I'm only surprised more coppers don't with the derelicts they have to deal with these days. JMO
