Former News of the World editor Andy Coulson - who is also a former Downing Street communications chief - and former News of the World Royal Correspondent Clive Goodman have been charged with making with illegal payments to public officials.
In a statement, the CPS states the allegations relate to "the request and authorisation of payments to public officials in exchange for information, including a Palace phone directory known as the “Green Book” containing contact details for the Royal Family and Members of the Household."
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