“Stars are public persons, so using footage of them is fine.” True or false? The law on using footage of persons of public interest is ambiguous even in such tightly-regulated countries as Germany. Different spheres of law intersect here: freedom of opinion and press freedoms collide with privacy and publicity rights. But a rule of thumb can be derived from the numerous cases which have arisen:

When images or audio from people who have become famous because of their status, office, talents or exploits (such as politicians, artists, actors, or sportspeople) are used in the context in which the individuals in question have reached prominence, the public interest in information is generally valued more highly than the right of individuals to privacy.

George Clooney and his wife walking on a red carpet could legitimately be used (in an editorial context) to illustrate the topic of George Clooney as an actor.
But if the same material was intended for use in an advertising context, say to suggest that George Clooney has a preference for a particular toothpaste, Mr. Clooney could raise objections. He would most certainly be in a position to raise objections if a marital row captured on camera by chance were to be shared with a wider audience (private sphere!) But if the marital row just so happened to take place on the red carpet – well, that would be a different story again.

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