I left top-secret files on a train

Senior civil servant Richard Jackson was used to dealing with top-secret government information.

It was a responsibility he took extremely seriously. In his office, everything was locked away with complicated combination locks, with briefcases of information physically chained to officials' wrists when travelling between buildings.

But on his way into the Cabinet Office one day, panic struck. Richard realised he had made a catastrophic mistake: he had left a secret file on the train.

Richard tells Dr Sian Williams about the horror of being thrust into the public eye, the feelings of shame that followed, and how he used the experience to help others.

Producer: Sarah Shebbeare

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