Mobile phone detection cameras to start targeting drivers by year's end

Mobile phone detection cameras will start targeting distracted Sydney drivers by the end of the year.

The detection cameras will photograph all passing cars, with a computer then identifying drivers who have a phone in their hand.

The system will ultimately check 123 million cars every year.

"What we need is a system to change the culture," Assistant NSW Police Commissioner Michael Corboy said. 

Based on numbers from a recent trial, it's estimated that more than 1 million drivers will be caught every year, attracting up to $348 million worth of fines.

Lawyers have told a parliamentary enquiry the legislation allowing the cameras reverses the onus of proof, and drivers will be assumed guilty.

"If I'm holding this glass while driving and my picture is taken, the law says, by force of law, this is a mobile phone, unless I can prove otherwise," Michael Mantaj of the Law Society of NSW said.

Bernard Carlon from the Centre of Road Safety said they were considering how road rules would keep up with other distractive technologies such as interactive dashboards, iPods and smart watches.