The footage showed a man, who had been convicted of distributing, making and possessing pornographic images of children, working at his local supermarket as part of a story focusing on a delivery he had made at work to a nursery school kitchen.
The man's mother complained that the video, which was published on February 21, was in breach of clause 10 of the PCC code, which prohibits the use of hidden cameras.
The Sun argued that the video, which was obtained by secret filming, was in the public interest, but agreed to remove it from its website and not reuse it unless 'there was a clear public interest to do so.'
While there was 'considerable public interest' in the story, the footage did not show the man making the nursery school delivery that was its focus, the PCC said in its adjudication.
"It was more difficult, however, to justify the taking and use of the audiovisual footage of the complainant’s son at work in the supermarket, given that the public interest element of the story related only to the delivery to the nursery. The Commission has always said that there must be a powerful public interest justification for the use of undercover filming," it said.
"There was insufficient justification for the filming on this occasion: there was no dispute that the complainant’s son worked for the supermarket, and the footage was not necessary to prove it," said the Commission in its ruling.