Green MP Caroline Lucas told the court she felt it was important to protest about fracking to prevent the UK from being locked into using more fossil fuels.
Ms Lucas said: "I'm haunted by the idea that my children and my children's children will turn round to me and say, 'What did you do about this overwhelming threat?'"
Her co-defendants were also cleared of both charges against them. They were Josef Dobraszczyk, 22, from Bristol; Ruth Jarman, 50, from Hook, Hampshire; Sheila Menon, 42, from north east London; and Ruth Potts, 39, from Totnes, Devon.
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Showers in the north, perhaps turning heavy at times but becoming drier in the south towards the afternoon.
Police have stepped up their search for Younes Abouyaaqoub, believed to be at the centre of the investigation into the Las Ramblas attack.
The proportion of adults in families owning more than one property has surged, while the number of those with no property wealth also grew.