Michael Perkins, 49, a road policing officer based at Chichester, appeared at Hastings Magistrates' Court charged with common assault and a public order offence.
He was found guilty of common assault against a woman prisoner he was transporting to custody in November 2011 after she had been arrested on suspicion of drink driving. He was fined £495 and ordered to pay £900 costs. He was found not guilty on a charge of using threatening words or behaviour.
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Tuesday morning's forecast for the east of the region
Tuesday morning's forecast for the west of the region
New criminal sanctions for those who fail to protect children from sexual exploitation are at the heart of new measures to be introduced.