Tuesday, December 04, 2018

NZTA, ANPR and privacy

Earlier in the month, we learned that NZTA would be trialling point-to-point speed cameras in the Waterview Tunnel. The cameras are a good road-safety tool to detect speeding, but they use automatic number-plate recognition (ANPR), and depending on how long the number plates are stored for and what is done with them, risks creating a UK-style database of people's public movements. So, I sent an OIA request to NZTA asking them for information about the system and any privacy policy or privacy assessment they had done for it.

The response is here. While they haven't completed the privacy work yet, there is some very good news about data retention:

In regard to the third part of your request, the system is being designed to hold an image of vehicles for the period of time it takes to travel between cameras. A second image will then be taken and only images of vehicles that have an average speed above the speed limit as well as being above the operating threshold (same as static cameras) will be retained by the system, all other images will be discarded. Infringement notices for speeding offences which are recorded by the cameras will be issued by the New Zealand Police.

Which seems pretty good: no storage, no database, so no huge privacy issue. We still need to keep an eye on it to ensure that it isn't subsequently modified to do those things, but if this is NZTA's default implementation of ANPR speed cameras and traffic counting, then we should be safe.