Former Whitehall adviser Patrick Rock has been bailed to appear at Westminster Magistrates Court on July 3 after he was charged over child abuse images.
Judith Reed, a senior lawyer with the CPS Organised Crime Division, said: "We have determined that there is sufficient evidence for a realistic prospect of conviction and that a prosecution is in the public interest."
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After the Indiana polls close, ITV News asked Ted Cruz supporters if they could back Donald Trump as the Republican presidential nominee.
With his massive victory in Indiana, Donald Trump can now not be stopped from becoming the Republican nominee.
Donald Trump has been projected to win the crucial Republican Indiana primary, prompting Ted Cruz to pull out of the race.