Farmers, miners, builders, real estate agents, media, scientists and police increasingly find drones useful. They can find livestock, spot needed repairs on bridges and buildings, take aerial photos of open cut mines, take glossy pictures from the air of property for sale, assist rescue operations, help in searches for missing folk, take high elevation pictures of landscapes and wildlife, track Antarctic ice floes and pursue baddies on the run.

But drones can also be a pest that invade privacy such as taking sneaky pictures of celebrity weddings, breach security of factories or farms, pose dangers to low flying aircraft such as helicopters, collide with birds and cause injury if they land on your head.

One 18 year old in the US attached a gun to his drone and fired at a target – something Connecticut police said wasn't illegal but should be. In Sydney a drone crashed into the harbour bridge alerting counter terrorism officers and firefighters also complain they are interfering with their operations.

In Australia aviation authorities acknowledge drones with cameras are now a fact of life and are everywhere. Until recently the cost of around $2000 has kept the numbers of drones down, but now drones are much cheaper. Aldi shops are selling them for $99.99.

Until now only recreational users could fly drones without a licence, and they have to weigh less than two kilos. Aviation regulations says drones have to be kept 30 metres from people, away from crowds, stay below 400 feet (122 metres) and kept five kilometres from airports.

If drones are used for a commercial purpose, operators need a licence and have to state what the drone will be used for.

The Civil Aviation Safety Authority is looking to relax these rules and allow commercial operators to fly drones without a licence. This will see the use of drones boom, especially by people chasing footage of police and fire operations.

But privacy laws are way behind the use of drones to peek over walls and into windows. So long as the drone operator is on public land he can't be charged with trespass.

The law isn't totally clear on whether drones can fly over private property without permission apart from the aerial safety regulations on the need to keep a distance. Privacy laws just haven't kept up with the technology and CASA says privacy laws are outside its orbit.

Drone laws are likely to be tested when a person sees a drone taking pictures through their bedroom window and demands the law protect them from the intrusion. Either that or they just shoot the drone down.

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