Speaking outside court, Crown Prosecution Service lawyer Greg McGill said, "DCI Casburn has been found guilty of misconduct in public office - not only did she seek to divulge confidential information, she sought to leak details of a case to the very newspaper under investigation".
"This is a very serious offence and the jury has today agreed that DCI Casburn's actions were criminal", he added.
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The £70 million F-35B jet arrived at RAF Fairford in Gloucestershire, two years after engine trouble postponed its first scheduled visit.