The guidelines also state that children (under-18s) will rarely face criminal charges for offensive tweets or Facebook statuses, for example.
Also if a message is swiftly deleted, blocked by service providers or websites or shown not to be intended for a wider audience, a prosecution is unlikely.
While intended for the CPS to make a decision whether to charge someone or not, the guidelines are also designed to offer early advice to police.
The interim guidelines take effect immediately and are now subject to a consultation process.
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A former Royal Marine who has recently been engaged has been killed in a climbing accident in the French Alps.
Through the day we'll see plenty of sunny spells but there will be a risk of showers too as they filter down from the northwest.
Pilots say they are rostered in 'illegally' and feel fatigued from working too many hours.