What future does investigative journalism have in an age when reporters face arrest and courts develop privacy laws? That was the question raised in a report published last week by the House of Lords communications committee.

The select committee’s starting point was that ‘responsible investigative journalism should be protected and encouraged, given its important role in our democracy’. Examples given to the committee included a BBC Panorama exposé of abuse at a care home, the Guardian’s investigation into phone-hacking and Daily Telegraph reports on MPs’ expenses.

But such stories cannot be obtained unless journalists are prepared to break the law, whether by making secret recordings, paying informants or even bribing public officials. Reporters may also break the laws of other countries, for example by breaching entry restrictions on journalists. Often, the desirable end is regarded as justifying the unlawful means, just as it is when MI6 officers break the laws of the countries in which they obtain intelligence.

English law offers some exemptions to journalists acting in the ‘public interest’. But the scope of that defence is far from clear and it does not apply to breaches of the Official Secrets Act, the Bribery Act or other legislation that could be used against investigative reporters. So what is to be done? The Lords report does not recommend redrafting all relevant criminal law to add a public interest defence: that would have produced endless arguments over what the public interest required in an individual case. Instead, it notes that journalists who act in the public interest have simply not been prosecuted.

That leads the committee to ‘urge the prosecuting authorities to publish their broad approach to determining which cases should be prosecuted or otherwise in cases where illegal activity undertaken by journalists in the course of an investigation might be considered to be in the public interest’.

During the fortnight between completion of the committee’s report and its publication, the director of public prosecutions promised to do just that. In evidence to Lord Justice Leveson’s inquiry into the culture, practices and ethics of the press, Keir Starmer QC undertook to draft a policy setting out the approach the Crown Prosecution Service (CPS) would take when considering whether to prosecute journalists for breaking the criminal law in the course of their work. An interim policy will bring together and clarify existing CPS practice and this will be adjusted if necessary in the light of public consultation.

Ahead of the policy statement, which will be published ‘in a matter of weeks’, Starmer disclosed the factors that struck him as relevant and which, presumably, are already taken into account in deciding whether journalists should be prosecuted. These include: the seriousness of the offence compared with the public interest in publication; whether there was an element of corruption; whether the offence involved threats or intimidation; whether criminal proceedings had been jeopardised; whether the public interest could have been served by lawful means; and the impact on victims of the conduct in question.

Another factor the CPS must take into account is the right to freedom of expression in article 10 of the human rights convention - which must, of course, be balanced against the protection of privacy under article 8. That balance was explored by the European Court of Human Rights in two recent cases brought against Germany. Both judgments, delivered on February 7, came down on the side of free speech.

In the first case, Axel Springer, publishers of the popular daily Bild, challenged injunctions preventing the newspaper from naming a well-known television actor who’d been arrested at the Munich beer festival and subsequently convicted of possessing cocaine. The actor was named at the time of his arrest but then obtained an injunction banning further identification. In Germany and some other continental countries, the media do not have an absolute right to name suspects accused or convicted of relatively minor criminal charges.

In its ruling, the Strasbourg court considered whether naming the actor had ‘contributed to a debate of general interest’; how well known he was; whether he had courted publicity; and how the newspaper had obtained its information. It concluded that the injunction obtained by the actor had been disproportionate to the legitimate aim of protecting his private life. Even so, the ban on identifying him remained in force and the actor was not named by the Strasbourg court or by the German press. His name was not particularly difficult to find on the internet, though.

The second case was brought by Princess Caroline of Monaco, who has been trying to keep her picture out of the newspapers for the past 20 years. She won a famous victory in 2004, establishing that even a princess had a right to a private life. Building on that ruling, Caroline challenged the publication of a photograph showing her on a skiing holiday at a time when her father, the reigning prince of Monaco, was suffering from poor health.

On that point, she lost. The behaviour of Prince Rainier’s children during his serious illness did indeed contribute to a debate of general interest, the court accepted.

One should not read too much into these judgments. On the very day they were delivered, the Strasbourg court threw out a freedom-of-expression challenge by The Times, whose publishers had challenged a finding that they were in contempt of court for disclosing jury deliberations in 2007. But, wherever you look, there does seem to be a welcome view among judges and politicians that we reporters still have a useful role to play.