LONDON The Independent Police Complaints Commission said on Friday it would meet the chief constable of Kent to discuss his force's handling of an environmental protest at a power station.
Lawyers for Camp for Climate Action say policing of a protest at Kingsnorth near Ashford in Kent last October was "unlawful, repressive and disproportionate."
They said police had used sleep deprivation and psychological tactics against the environmentalists, including playing loud recordings of Richard Wagner's "Flight of the Valkyries" and the Clash hit "I Fought the Law and the Law Won."
The camp was held to protest at plans by German energy company E.ON to replace its existing 1,940 megawatt coal-fired-plant at the site with what it says will be cleaner coal units.
"No Climate Camp protester has ever been convicted of any violent offence," the lawyers said in a dossier launched by the Liberal Democrats.
"Yet the Climate Camp continues to experience disproportionate and repressive policing, and seems to be being targeted by the police as single-issue domestic extremism."
The Liberal Democrats called for a public inquiry into the police tactics.
"What happened at the Climate Camp was deeply disturbing and part of what seems to be a disturbing national trend," said the party's justice spokesman, David Howarth.
Kent Chief Constable Michael Fuller said he had voluntarily referred the dossier to the IPCC.
"This document makes a number of allegations. Kent Police's policy has always been to be open and transparent in everything we do and this will be no different," he said
"If we find officers have failed to meet the very high standards we expect, then we will act."
The IPCC said it was waiting for further information and would meet Fuller next week.
(Editing by Steve Addison)