Brighton Pavilion MP Caroline Lucas was arrested outside energy company Cuadrilla's exploratory oil drilling site in Balcombe, West Sussex, last August 19.
She was among a group of protesters who had linked arms outside the site, which had become a national focal point for anti-fracking protests.
During the trial at alongside four co-defendants, Lucas, 53, said she "wanted to express solidarity" by protesting peacefully. She was found not guilty of the two charges she faced - wilful obstruction of a public highway and breaching an order under Section 14 of the Public Order Act.
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