A video journalist today vowed to fight police demands for his footage of a demonstration to be handed over.
Greater Manchester Police are demanding that Jason Parkinson hand over footage of a demonstration by the fascist English Defence League and a Unite Against Fascism counter-protest in Bolton in March 2010.
The National Union of Journalists gave Mr Parkinson its "full support."
Mr Parkinson won a landmark court case last May, refusing to give Essex Police footage of the Dale Farm travellers site eviction.
But police will take him to court on Monday to force him to turn over the Bolton tape.
Mr Parkinson said he was unwilling to hand over unpublished material.
"Journalists report the news and are not evidence-gatherers for the police or anyone else," he said.
He pointed out that a loss of independence could put reporters at greater risk of attack during future demonstrations.
As Aslef's annual assembly of delegates begins in Edinburgh tomorrow the general secretary explains the challenges his members - and workers across the country - face