verification, page-2

This is what the RTA says:

"How do I know that information recorded is secure?

The original recorded images are stored electronically on a WORM (Write Once Read Many) disk, which cannot be overwritten or altered. A security indicator is also produced when the file is written to the disk and should any attempt be made to tamper with the image at any stage, this is obvious to the relevant technician viewing the image.

Where the image is electronically transferred, all images and relevant information (such as time, date and location) is encrypted. Thus, the image cannot be viewed without the appropriate encryption key.

The original image forms the basis of the evidence produced in court. In line with legislative requirements, the photographs from fixed, digital speed cameras can be tendered as evidence in court, together with appropriate evidentiary certificates signed by an expert."

From http://www.rta.nsw.gov.au/roadsafety/speedandspeedcameras/fixeddigitalspeedcameras/howdofixeddigitalspeedcameraswork.html

Also - if digital photos are not acceptable as evidence in a court of law, there would be all sorts of ramifications. Think surveillance cameras and terrorist attacks for example.