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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Holly has Tuesday's forecast for the east of the region.
Holly has Tuesday's forecast for the west of the region.
The proposal will see the introduction of a discounted railcard for 26-30-year-olds, as the government looks to lessen the cost of living.