Drivers repeatedly caught using a mobile phone behind the wheel will face double demerit points from Tuesday under a new crackdown by the state government.

The new laws, which were flagged earlier this year, will see drivers lose three demerit points for a first offence.

If they are caught using a phone again within 12 months, a further six points will be deducted.

Acting Assistant Commissioner Dale Pointon driver behaviour had changed from people holding phones up to their ears to make calls to now looking down while texting.