The NSW Police Integrity Commission can now pursue crooked NSW cops with NSW Police helicopters and small aircraft at night without lights.

CASA published an exemption giving the PIC these powers on Friday.

The exemption adds to the uses of a growing constellation of dark aircraft being used for surveillance, anti terrorism and law enforcement purposes in Australian night skies.

This means that the black hovering or slowly circling object you might see against the background glow of the night sky over the trouble prone further western suburbs of Sydney might not just be station keeping waiting for idiots to shine lasers at jets, or tracking the action around bikie hot spots or drug labs.

It might be listening to a conversation between crooked constable X and caucus member Y in the back room above a brothel.

Dark choppers have been a feature of police operations in Australia in recent years. And have been used in training and “real” covert operations by the SAS for considerably longer.

They can see people carrying unusual objects in car parks or near bridges or other infrastructure. They use thermal imaging and can have sophisticated capabilities to see clearly types of materials and integrate what is seen with detailed maps of installations, buildings and other surface features.

They can communicate with ground commands with other air and surface response units.

But as far as non-military equipment is concerned, CASA has to publish exemptions which officially tell other pilots that they may, conceivably, find themselves in the vicinity of dark aircraft.

And the safety rules require these covertly operated flights to listen to the radio frequencies used by normal traffic, and if challenged turn on their lights and identify themselves to any other aircraft, or air traffic control, on demand.

In real life however, the covert flights are in places so low and sometimes so close to hills or buildings, that normal aircraft would not come near them.

On Friday, entirely by coincidence, CASA also published another exemption for the Surveillance Australia Dash 8 turbo-prop, used by Customs to detect people and drug smugglers, to operate without lights from Lord Howe Island.