Almost two-thirds of drug drivers detected in Victoria in the last year were caught during daylight hours, say Victoria Police.
Around 5200 of the 8400 drug drivers detected in the last financial year were caught between 6am and 6pm.
More than twice as many were caught on a weekday than the weekend, with 1400 detections on a Friday, ahead of Saturday, Sunday and Thursday.
The data is based on positive secondary drug tests which have been confirmed through laboratory analysis.
Victoria Police conducts around 150,000 roadside drug tests a year.
Every highway patrol car has the ability to test for drugs alongside the dedicated drug bus fleet.
Drivers caught drug driving face heavy fines and a loss of licence.
First-time drug drivers will be fined $593 and have their licence suspended for six months; they must also complete a drug driver program within three months or their licence or learner permit will be cancelled.
Repeat drug drivers face fines of up to $23,710 and will have their licence cancelled for at least 12 months.
Police also have the power to impound a vehicle for drug driving offences.
"People might think illicit drug use is confined to the weekend but the reality is our members are seeing people getting behind the wheel on illicit substances right across the week," said Acting Inspector Kevin Vincent, State Highway Patrol.
"That's why we have highway patrol vehicles and our drug bus fleet out day and night to keep all road users safe.
"We are out anywhere, anytime testing for drugs. There really is nowhere to hide.
"Drugs cause more deaths on our roads than alcohol – it's just not worth the risk."
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