A woman who claimed she was assaulted by a Wiltshire policeman in a cell was so drunk she was an unreliable witness, an appeal court has heard.
Sgt Mark Andrews, who was filmed dragging Pamela Somerville through Melksham police station, is appealing against his conviction and sentence.
His barrister Jeremy Barton told Oxford Crown Court Ms Somerville had refused to take a breath test.
She told the court that was untrue and no charges were pressed against her.
Andrews was found guilty of actual bodily harm and jailed for six months following the incident, which happened in July 2008.
He spent six days in prison, but was released on unconditional bail pending his appeal.
Mr Barton suggested to Ms Somerville that she had refused to take a breath test after being found asleep in her car because she knew how drunk she was.
However, Ms Somerville, who required stitches to an injury above her eye after the incident, denied this.
She was arrested after being found asleep in her car near her Colerne home and had been detained for failing to provide a sample for a breath test.
She denied any wrongdoing and the charges against her were later dropped due to insufficient evidence.
The hearing, which is expected to last a week, was adjourned until Wednesday.