The ruling is expected to encourage courts throughout Europe to take a stronger line over the publishing of images of celebrities who do not have official functions or who do not seek public attention.
Forty-seven year old Princess Caroline von Hannover has been campaigning in various European countries for over 10 years, fighting against the publication of photographs about her private life.
The daughter of Prince Rainier of Monaco and film star Grace Kelly lives mostly in France, where her prior agreement is necessary for the publication of any photos not showing her at an official event. However there is nothing to stop photographs being taken and then published in another country, such as the UK or Germany, which rely on a "public interest" requirement to justify publication.
The Princess has on several occasions unsuccessfully applied to the German courts for an injunction preventing any further publication of a series of photographs that had appeared in the 1990s in the German magazines Bunte, Freizeit Revue and Neue Post. She claimed that they infringed her right to privacy and her right to control the use of her image.
The photos showed the Princess involved in such innocuous activities as skiing, shopping, leaving a restaurant or simply out walking.
In a landmark judgment in 1999 the German Federal Constitutional Court granted the Princess an injunction regarding some of the photographs - in which she appeared with her children - on the ground that their need for protection of their intimacy was greater than that of adults.
However, the Constitutional Court considered that the Princess, who is undeniably a contemporary "public figure", had to tolerate the publication of photographs of herself in a public place, even if they showed her in scenes from her daily life rather than engaged in her official duties. The Court explained that her right to privacy was overridden by the freedom of the press and the public's legitimate interest in knowing how such a person generally behaved in public.
The European Court of Human Rights
The Princess took her case to the European Court of Human Rights (ECHR) in Strasbourg, arguing that the decisions of the German courts infringed her right to privacy and her right to respect for her family life, both of which are protected under the Convention.
The Court ruled that there was no doubt that the publication by the German magazines of photographs of the Princess in her daily life, either on her own or with other people, fell within the scope of her private life. The Convention, it decided, was therefore applicable.
The real issue was how and where to balance the need for protection of the Princess's private life against freedom of expression, which is also guaranteed under the Convention.
The Court ruled that although freedom of expression also extended to the publication of photographs, this was an area in which the protection of the rights and reputation of others took on particular importance, explaining:
"The present case does not concern the dissemination of 'ideas', but of images containing very personal or even intimate 'information' about an individual. Furthermore, photos appearing in the tabloid press are often taken in a climate of continual harassment which induces in the person concerned a very strong sense of intrusion into their private life or even of persecution."
The Court considered that the decisive factor in balancing the protection of private life against freedom of expression should lie in the contribution that the published photographs and articles made to a debate of general interest.
In the case before it, said the Court, the photographs showed Caroline von Hannover in scenes from her daily life, and thus engaged in activities of a purely private nature. The Court noted in that connection the circumstances in which the photographs had been taken: without her knowledge or consent and, in some instances, in secret. It was clear that they made no contribution to a debate of public interest, since she exercised no official function and the photographs and articles related exclusively to details of her private life.
Furthermore, said the Court, while the general public might have a right to information, including, in special circumstances, on the private life of public figures, they did not have such a right in this instance.
The Court considered that the general public did not have a legitimate interest in knowing Caroline von Hannover's whereabouts or how she behaved generally in her private life even if she appeared in places that could not always be described as secluded and was well known to the public.
The Court reiterated the fundamental importance of protecting private life "from the point of view of the development of every human being's personality" and said that everyone, including people known to the public, had to have a "legitimate expectation" that his or her private life would be protected.
The Court also stressed that "increased vigilance in protecting private life is necessary to contend with new communication technologies which make it possible to store and reproduce personal data".
"This also applies to the systematic taking of specific photos and their dissemination to a broad section of the public," said the Court.
In the Court's opinion, the German courts had not struck a fair balance between the competing interests, and there had been a violation of the Princess's right to privacy.
Having made this ruling there was no need to consider the issue of respect for the Princess's family life, said the Court.
Mattias Prinz, lawyer for the Princess, told Reuters: "This is very good for my client and for all people in Europe because the court is raising the standard of protection of private life to a level higher than in Germany – to the level of France".
In practice, the ECHR has no authority to overrule the original decision of the German Constitutional Court, but can fine the German Government if the ruling is not changed. Germany has three months to appeal.
The ruling will also have an impact on how privacy is enforced within the UK, following the bringing into force of the 1998 Human Rights Act. This incorporated the European Convention on Human Rights into UK law, and means that judgments of the ECHR should now be taken into account by UK courts.
Dr. Chris Pounder of Masons, the firm behind OUT-LAW.COM, and Editor of Data Protection and Privacy Practice, said: "The ruling is important as it specifies that when UK newspapers publish pictures in future on grounds of serving the 'public interest', there has to be some contribution towards a debate of general interest. Pictures which depict a person's private life in the absence of such a contribution - for instance, merely to titillate the reader - could become actionable on human rights grounds - even if the photos are taken in a public place."
Footnote: Dr Chris Pounder was a consultant with Pinsent Masons until September 2008. He now runs a new training business, Amberhawk.