My palms sweat when I think about it now, but I was once party to a plot to smuggle plastic explosives into the Palace of Westminster.

I was a reporter on a science magazine which had published a claim that equipment newly installed to protect parliament from IRA bombs wouldn’t work. We’d tested the detector at a trade show by recruiting a friendly expert to carry a small quantity of (licensed) explosives through it. Unfair, said the device makers, who claimed to have turned down the sensitivity of the exhibited device because of the known presence of ordnance in the hall. So we resolved to repeat the experiment in parliament itself.

Even in those innocent days ­- this was 30 years ago - we had enough sense not to go through with it. But if we had we’d have claimed a public interest in calling attention to complacency around security measures (which, we maintained, ‘real’ terrorists already knew wouldn’t work).

Frankly, I don’t think we'd have deserved much sympathy. But what about less extreme journalistic stunts involving illegal behaviour? When does the public interest in a free press outweigh the public interest in not letting individuals get away with crimes?

This may seem a strange question to ask when some 50 journalists have been arrested in connection with phone hacking and corruption investigations. But according to Keir Starmer, director of public prosecutions, it’s exactly the right time if public confidence in the criminal justice system is to be preserved. A consultation closes next month on a set of interim guidelines for prosecutors on assessing the public interest in cases affecting the media.

I think they’re important: not because they’ll end up putting too many of my colleagues in prison, but because they have the potential to let too many claim they can break the law with impunity.

Starmer says the guidelines contain no new principles - he says that every prosecution already involves consideration of the public interest in proceeding, once the evidential test is past. He also stresses that every case must be considered on its own individual facts and merits. However, the guidelines seem to create a special further test in cases involving article 10, right to freedom of expression.

The guidelines list five examples of illegal conduct that is capable of serving the public interest. Top of the list is conduct capable of disclosing a criminal offence. Other examples include conduct that discloses when a person is failing to comply with legal obligations and revealing miscarriages of justice.

But also there is ‘Conduct which is capable of raising or contributing to an important matter of public debate.’ Starmer’s example is the reporting of the parliamentary expenses scandal, which to a large extent did not involve outright criminal behaviour but was certainly an important matter of public debate.

While few people would argue with that example, I think there’s a danger. While the guidelines stress that journalists are afforded no special status under the criminal law, these guidelines seem to be written with the traditional Fleet Street or Broadcasting House reporter in mind. For better or for worse, these are dying breeds. I suspect that, once the current prosecutions are out of the way, the main use of these guidelines will be in cases involving activists self-publishing in blogs or other new media. Every politically motivated vandal is a journalist nowadays, and all would claim to be ‘raising or contributing to an important matter of public debate’.

The instant answer - likely to be bolstered by the verdict of the Leveson inquiry - would be some sort of regulation in which a ‘responsible’ licensed press would enjoy greater access to a public interest test than the tabloids or bloggers. I’m afraid I’d find that even scarier. In his 1978 play Night and Day, Tom Stoppard pointed out the slippery slope of trying to ringfence a quality press: ‘It's indivisible. Junk journalism is the evidence of a society that has got at least one thing right, that there should be nobody with the power to dictate where responsible journalism begins’. That still applies today.

The CPS consultation closes on 10 July.

Michael Cross is Gazette news editor

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