By Martin Rosenbaum
BBC Freedom of Information Unit
Prosecutions of some Greenham Common protesters in the 1980s succeeded because police were able to "paper over the evidential gaps", documents show.
The Greenham Common protest lasted for 19 years
The police were fortunate that more cases did not collapse, a senior police lawyer wrote in 1984.
But they got away with it as protesters were so intent on making political statements in court they "overlooked the prosecution's weaknesses".
The documents were obtained by the BBC under the Freedom of Information Act.
The controversial and high-profile women's peace camp outside the RAF base at Greenham Common in Berkshire was a leading symbol in the 1980s of the campaign against nuclear weapons.
The prosecution admissions were made in an analysis of Greenham court cases prepared in March 1984 for the Chief Constable of Thames Valley Police, Peter (now Lord) Imbert.
Its author was the force's chief prosecuting solicitor, Colin Hoad.
Referring to a case where 70 women on one demonstration were arrested by a single officer, the report states: "The prosecution was very fortunate that this case (and similar ones) did not collapse completely.
"In the event it proved possible to paper over the evidential gaps."
Mr Hoad goes on: "Those problems ... could have been seriously exploited by any competent defence advocate.
"This did not happen largely because the women were so intent on seeking to justify their actions by political considerations and on using the Court as a forum for publicity, that they overlooked the prosecution's weaknesses."
Numerous prosecutions were brought against the peace campers, who generally defended themselves in court.
They were opposed to the siting of American cruise missiles at the Greenham base.
The report also makes clear some difficulties faced by the police due to the tactics of the protesters.
"We have reached a position where photographs are almost of no evidential value at all", it states, because "on almost all the files the defendant has her hands and arms covering her face".
Mr Hoad recommended that the police adopt new procedures in some cases of alleged obstruction of the highway.
This "is absolutely essential if the allegation is that the obstruction is caused by 'dancing' in the road (a type of case where the acquittal rate has been extremely high)".
The disclosure does not surprise Sarah Hipperson, who was a prominent figure in the peace camp.
She said: "At first we didn't have time to go to libraries to look these things up. As we settled down we did more of that and got better at it.
"But the prosecution's weaknesses wouldn't have concerned us as much as the big picture," she added. "Our concern was the arguments about nuclear weapons."
Lord Imbert does not remember receiving the report. He said: "I can't recall knowing of any concern from Colin Hoad. Generally they were watertight cases. I hope they were in all cases."
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