Detective Chief Inspector April Casburn has been found guilty at Southwark Crown Court of misconduct in public office for trying to sell information to the News of the World.
Casburn, 53, committed a "gross breach" of the public's trust by calling the now-closed tabloid and offering details of the phone-hacking investigation in return for payment.
She telephoned the Sunday newspaper early on September 11 2010 and spoke to journalist Tim Wood, complaining about pressure from Lord Prescott over the probe and giving the names of two former NotW journalists under investigation - Andy Coulson and Sean Hoare.
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Nearly 38,000 runners will hope to complete Sunday's London Marathon making it the biggest event in its 35-year history.
Rain across central Britain with longer, intense downpours with thunder in places this evening. A lucky few will stay sunny and dry.
Planning on going to the London Marathon tomorrow? Read our handy guide first!