Mr Wright said the incident involving the couple having sex on the patio happened on July 28 2008 when the aircraft was piloted by Loosemore, with Pogmore and Lucas as the observers.

Earlier on the same day, the helicopter was used to film a couple sitting naked by a caravan on a campsite used by naturists, also in South Yorkshire.

The prosecutor said: "Although naturists expect to be seen naked by other naturists, they do not expect to be monitored by the crew of the police helicopter."

The jury was shown the video recording of the naturists shot from the helicopter as well as two more recordings of people sunbathing naked.

Footage shot on August 23 2007 - when the pilot was Reeves and the observers were Pogmore and Walls - appeared to involve the aircraft circling a garden where a woman was sunbathing without clothes on a lawn.

Mr Wright said the woman was with two daughters - aged 18 and 15 - who were wearing bikinis and an eight-year-old daughter, who appeared to be fully clothed in the footage.

The prosecutor said: "There is self-evidently no legitimate policing purpose connected to orbiting her home and using equipment to film her naked body."