A landmark High Court ruling has blocked an attempt by the police to seize large quantities of TV film footage shot during high-profile evictions at a travellers' site.
Judges today quashed orders obtained by Essex Police requiring the production of all footage held by several news organisations showing the clearance of the Dale Farm site near Basildon last October.
There were scenes of violence as the police dismantled the Dale Farm barricades, but the High Court ruled that Judge Gratwicke, who made the orders at Chelmsford Crown Court in February, had gone wrong in law.
Laying down guidelines for the future, Lord Justice Moses and Mr Justice Eady, sitting in London, said the police were entitled, under the 1984 Police and Criminal Evidence Act (Pace) to seek material "likely to contain evidence" of offenders committing acts of violence during outbreaks of public disorder.
But they warned that "the neutrality of the press" must be protected.
Applications for production orders had to be backed up by "clear and specific evidence" that the material sought would be "of substantial value" in seeking to prosecute violent offenders.
In the Dale Farm case, there was inadequate evidence, the judges ruled. The police wanted access to "a vast amount of film" for "a merely speculative exercise".
Lord Justice Moses also said Judge Gratwicke "failed to give sufficient weight to the inhibiting effect of production orders on the press".
The ruling was a victory for the BBC, Independent Television News, BSkyB, Channel 5, Hardcash Productions and freelance video journalist Jason Parkinson who jointly brought the legal challenge and complained production orders were increasingly being used as "fishing expeditions" and threatening to turn journalists into "coppers' narks".
Later, ITN chief executive John Hardie said: "This landmark decision is a legal recognition of the separate roles of the police and independent news organisations.
"We fought this case on a matter of principle - to ensure that journalists and cameramen are not seen as agents of the state, and to protect the safety of our staff."
Fran Unsworth, the BBC's head of news gathering, said: "Journalists must maintain their independence, must not be seen as evidence gatherers and must not have their safety compromised.
"The guidance makes it clear that applications for un-broadcast material must be supported by proper evidence, must be focused and proportionate and the court has acknowledged that the over-use of production orders may make it harder for the press to do its job."
Chief Constable Andy Trotter, who speaks for the Association of Chief Police Officers (Acpo) on media issues, said: "This judgment brings clarity to this area of law and will assist police forces and the media to deal with similar matters in the future.
"While police forces have the duty to pursue all lines of enquiry when investigating crimes, any future application for the production of unused material must have specific and clear evidence and grounds for that application to succeed.
"The media plays a vital role in helping the police communicate with the public in the fight against crime, and this judgment assists the police and the media with what had become a contentious issue between them."
Mr Justice Eady described the Dale Farm clearance was a large-scale operation "in the full glare of publicity". Police were supporting Basildon Borough Council's attempts to enforce a court order requiring travellers to be moved from the site.
The operation attracted widespread news coverage and the court was told 16 police officers were injured during the operation.
It was understood that three people were arrested on charges of violent disorder, plus a further 10 for other public law offences, and it was thought that 15-20 other people suspected of violence had yet to be identified.
Most of the violence seemed to have happened during the first hour or so of the police operation, when film footage showed officers attacked with missiles and weapons, including a spade.
They were also "urinated from above by people located on scaffolding".
The production orders required each news organisation to produce within seven days all their film footage - covering 17 hours on October 19 and nine hours the following day.
The police estimated that altogether the journalists would have to hand over more than 100 hours of footage, incurring considerable time and expense, according to media lawyers.
Gavin Millar QC, appearing for the media, argued at a one-day hearing last month that the applications for orders were excessive, unlawful and a disproportionate interference with the media's right to freedom of expression under Article 10 of the European Convention on Human Rights.
Mr Millar said there was widespread concern that such applications were being made "impermissibly on an unfocussed and scattergun basis".
Essex Police said there were reasonable grounds for believing that the journalistic material being sought "would be likely to assist" investigations.
Mr Justice Eady said in today's ruling it was difficult to dispute there was a real public interest in tracing people involved in public disorder or violence.
But that had to be set against the level of interference with the media's Article 10 rights inherent in production orders.
He said it had been for Essex Police to demonstrate that the "degree of interference" and the wide scope of the production order was "necessary and proportionate" - but there was "nothing to justify any such conclusion".
The judge said: "Because the cupboard was bare when it came to demonstrating that the material would be of substantial value to the police investigation, the claimants were denied a fair opportunity to demonstrate to the (Chelmsford) court why much, if not the totality, of their material was unlikely to be of any assistance."
Disclosure orders could be "of great value" said the judge but "can never be granted as a formality".
Lord Justice Moses agreed and said: "The judge (Judge Gratwicke) should have feared for the loss of trust in those hitherto believed to be neutral observers, if such observers may be too readily compelled to hand over their material.
"It is the neutrality of the press which affords them protection and augments their ability freely to obtain and disseminate visual recording of events.
"There was no basis on which the judge could dismiss the evidence of a number of witnesses of the effect of handing over a vast amount of film, whether under compulsion or no.
"Still less should he have done so in the furtherance of a merely speculative exercise."
The judge added that nothing he had said should discourage the police from seeking to obtain material "likely to contain evidence to assist in successfully prosecuting those who participate in violence".
"But it is not easy to do so and it should not be easy."
The judge said he hoped today's ruling would assist in identifying "the need for specific and clear evidence and grounds for making production orders".