Scotland Yard threatening to force The Guardian to reveal its confidential sources of information for stories relating to the News of the World phone-hacking scandal is one more example of misuse of the Official Secrets Act.

More than 30 years ago, a certain American newspaper brought down a certain president by courageously exposing his wrongdoings entirely on the strength of information supplied by an anonymous source. It was not until some quarter of a century later that the real identity of Washington Post's source for its expose of the Watergate scandal was revealed. Nearer home, the identities of many British officials who helped the media expose the excesses of the Iraq invasion still remain unknown. In a stark example of how dangerous it can be for an informant to have their identity disclosed, British weapons expert David Kelly was harassed to the point after being named the source of a damaging BBC story, where, ultimately, he was driven to taking his own life. The report claiming that the Government “sexed up” intelligence about Saddam Hussain's weapons capability was based on an off-the-record conversation with Dr. Kelly.

Not for nothing, it is argued, is the right of a journalist to protect his or her sources guaranteed under the European Human Rights Act which recognises it as a “cornerstone” of a free press. Yet, last week, Scotland Yard came close to wrecking it after it threatened to force The Guardian newspaper to reveal its confidential sources of information for stories relating to the News of the World phone-hacking scandal.

Last Friday, the Metropolitan Police was to have applied for a court order to compel The Guardian to hand over documents that may disclose its reporters' sources. Bizarrely, it invoked the notorious Official Secrets Act, normally used to prevent espionage or deal with threats to national security, to justify its extraordinary demand. It claimed that the stories were based on unauthorised leaks and therefore the newspaper was in “potential breaches” of the Misconduct in Public Office and the Official Secrets Act.

In the end, following widespread condemnation of its ill-judged move, better sense prevailed and the Met pulled back from the brink. But the threat has not gone away as it has left open the possibility of revisiting the issue, sparking a debate on the profound implications such an attempt would have for press freedom, especially investigative journalism.

Lawyers, media experts and free-speech campaigners are unanimous in holding the view that compelling journalists to disclose their sources is justified only when such disclosure is in obvious public interest or when protecting a whistleblower threatens national security. None of these considerations applied in the present case whose sole purpose appeared to be to target whistleblowers within the Met, especially the source or sources behind a Guardian report in July that, for the first time, revealed the scale of the hacking scandal. The revelation that the News of the World hacked the phone of a murdered schoolgirl Milly Dowler in search of stories provoked national outrage forcing Rupert Murdoch to close down the 160-year-old tabloid amid a wave of high-profile resignations at his media group News International. The report also prompted criticism that the Met had been deliberately lax in investigating the scandal because of its close links with the Murdoch media.

The Met's threat to The Guardian was widely perceived as vindictive with even the Murdoch-owned Times calling it a “punitive measure.”

“The law is being invoked in this case not to protect the public interest but as a punitive measure to curb journalistic inquiry and pursue a sectarian and self-interested campaign,” it commented.

Prominent writers, including Salman Rushdie, Hanif Kureishi, Kamila Shamsie and playwright David Hare, warned in a joint statement that forcing journalists to disclose their sources would do “irreparable damage to the free press'' with “serious implications for the public's ability to discover wrongdoing.”

Free speech campaign group Index on Censorship said it was “a shocking move to intimidate the media” while The Guardian called it “an unprecedented legal attack on journalists' sources.” Its Editor-in-Chief Alan Rusbridger vowed to “resist this extraordinary demand to the utmost.” He has since welcomed the police climbdown but said: “We would have fought this assault on public interest journalism all the way.”

The National Union of Journalists (NUJ) argued that protection of sources was “an essential principle… repeatedly reaffirmed by the European court of human rights as the cornerstone of press freedom.”

“Journalists have investigated the hacking story and told the truth to the public. They should be congratulated rather than being hounded and criminalised by the state… The NUJ shall defend it. In 2007, a judge made it clear that journalists and their sources are protected under article 10 of the Human Rights Act and it applies to leaked material. The use of the Official Secrets Act is a disgraceful attempt to get round this existing judgment,” said its general secretary, Michelle Stanistreet.

To Bob Satchwell, executive director of the Society of Editors, the police action struck as “outrageous, pointless and baffling.” The Official Secrets Act, he said, was designed to protect national security and there was “no justification” to use it in this case.

This is not the first time that British police have resorted to legal bullying of the media. Distinguished journalist Harold Evans recalled his own run-ins with authorities when he edited the Sunday Times and The Times. Writing in The Observer, he said: “I had a few tangles with the courts in my years editing the Sunday Times and The Times. The thalidomide case (the newspapers' ground-breaking investigation into the damaging effect of Thalidomide, a sedative drug prescribed for morning sickness) was the most well known, and resolved on the side of free speech only by a ruling of the European court of human rights (which imposed a duty of reform on the British government).''

Invoking the Official Secrets Act was a “cavalier abuse” of a law that was intended “to protect national security, not to cover up negligence and corruption, least of all to justify an assault on the very newspaper that exposed the original crime while the police, politicians and the press walked by.”

According to leading human rights lawyer Geoffrey Robertson, the Met action was in “blatant breach” of the European Human Rights Act which guaranteed protection of news sources for the “very good reason” that they would dry up if after being promised anonymity they were to be exposed and prosecuted.

In a well-known case involving a young British reporter Bill Goodwin, who refused a local court order to disclose his source, the European Court of human rights ruled that “the watchdog role of the media would be imperilled if government agencies were able to force disclosure of sources in order to subject them to reprisals.”

There have been calls for the Official Secrets Act, enacted 100 years ago and updated in 1989, to be repealed and replaced with a legislation with the explicit purpose of protecting national security. Currently, it gives sweeping powers to the authorities to suppress in the name of national security any information they may deem inconvenient. In a withering attack, The Times writer Ben Macintyre said the Met's move was “only the latest attempt by officials to deploy this ancient, flawed legislation to intimidate journalists and plug the leakage of inconvenient truths.”

Arguably, Britain has the world's most free media and, as the phone hacking scandal showed, it also often enjoys a cosy and self-serving relationship with both the police and politicians. Yet, from time to time when it is seen to behave “inconveniently,” the state lets it be known who the boss is. Former Labour Prime Minister Tony Blair was so enraged by the media criticism of his policies that he launched a vituperative public attack accusing it of behaving like a “feral beast” and called for it to be tamed through increased regulation.

The BBC faced the full wrath of the Blair government for its critical coverage of the Iraq invasion. Both its chairman Gavyn Davies and director-general Greg Dyke were forced to resign in 2004 in the wake of a public inquiry that, in the words of Mr. Davies, reached the “bald conclusion” that the broadcaster's criticism of the government's intelligence claims were unfounded. Journalist Andrew Gilligan who reported Dr. Kelly's doubts about the veracity of the claims also lost his job.

The current case has prompted comparisons with the controversy in 1970s over the publication of Labour politician Richard Crossman's diaries. The then Labour Government sought to block their release on grounds that they breached the principle of confidentiality but the case was thrown out. The police have form on using the Official Secrets Act to intimidate its perceived enemies. The Guardian case is simply the latest in a string of cases over the past decade where the Act was invoked but then dropped when the heat got too much to bear.

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