Traffic enforcement officers pulled over a driver with a reading too high for the roadside RBT device in Roleystone.
A Holden Commodore was stopped at 10:50am on Croyden Road in Roleystone on Wednesday March 13.
The 51-year-old male driver from Kelmscott was barely conscious according to police, and his roadside test was too high for the machine.
Police say "it appeared he'd stocked the front seat of his party bus so he'd never run out."
Once back at the station his reading was 0.338% calculated to be 0.307 grams of alcohol per 100ml of litres of breath at the time of occurrence.
That is almost seven times the legal limit.
The man has been charged with driving a motor vehicle under the influence of alcohol.
He is due to face the Armadale Magistrates Court in June.
The front passenger seat of the man's vehicle. Picture: WA Police.
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