A police officer has been jailed for six months after he was caught on CCTV throwing a woman into a cell, badly injuring her.
The footage also shows Sgt Mark Andrews dragging Pamela Somerville, 59, through Melksham police station in Wiltshire.
Andrews, 37, was convicted of causing her actual bodily harm. He has been suspended from duty and will face a police misconduct hearing.
Patrick Geenty, from Wiltshire Police, said he was "a disgrace" to the force.
Ms Somerville was arrested in July 2008 after being found asleep in her car.
She had been detained for failing to provide a sample for a breath test but denied any wrongdoing. The Crown Prosecution Service said the charges were later dropped due to insufficient evidence.
Ms Somerville was taken to the Royal United Hospital in Bath after the attack and needed stitches to a gash above her eye.
Andrews was found guilty on 13 July after a trial at Oxford Magistrates' Court.
Passing sentence, Deputy District Judge Peter Greenfield said Andrews had abused his position of trust and only a custodial sentence was appropriate.
'Let colleagues down'
He said: "In my view, you presided over an atmosphere of bullying and intimidation upon Ms Somerville which culminated in the cell later that morning.
"I regard that a gross breach of trust placed upon you by Ms Somerville.
"I consider that right thinking members of the public will be appalled and totally saddened by your actions as a police officer."
Speaking outside court, the assistant chief constable of Wiltshire Police, Patrick Geenty, apologised for what the judge said was a "gross breach of trust".
"This was a disgraceful incident which breached the standards of care which every police officer gives to the public.
"There is no place in Wiltshire Police for an officer like this. I fully support the comments of the judge and the sentence that he has handed down today.
"The officer let the public down, he let his colleagues down and he has let himself down. He was a disgrace.
"I am proud of the officer who came forward and reported him to his supervisor.
"That officer upholds the standards of the service that we all expect."
Andrews was suspended on full pay following his conviction and is expected to lose his job.
His lawyer, Jeremy Barton, said he would be appealing against the sentence.
Mr Barton said Andrews had received death threats and that the stress from the court case had put his family under great strain.
"Right from the very outset, he's expressed sorrow for the injuries that she received while in his custody," he said.