Yorke Mid North Local Service Area Superintendent Mark Syrus says selfish drivers who make stupid decision put innoncent lives at risk.
"Most people do the right thing and we commend them for that," he said.
"But several people in the Port Pirie area over the Anzac long weekend refused to heed the warnings, were caught, and will now face the consequences."
Four drivers were detected drink or drug driving in Port Pirie over the Anzac Day long weekend.
Just before midnight on Friday, April 23, police observed a vehicle travelling towards them on the wrong side of Esmond Road. The vehicle just missed hitting the curb before returning to the correct side of the road.
Patrols stopped the blue Ford sedan and spoke to the driver, a 57-year-old man from Tailem Bend, who exited the car and needed assistance to stand due to being unsteady on his feet.
He was submitted to a breath analysis and returned an alleged positive result of 0.124. The driver was issued a six-month instant loss of licence and had his vehicle impounded for 28 days.
On Sunday, April 25, patrols stopped a sedan for a mobile driver test on Esmond Road where the driver of the vehicle, a 33-year-old man from Port Pirie, was subjected to alcohol and drug testing.
The man allegedly tested positive to methamphetamine and was found to be in possession of the same drug.
He was issued with a drug diversion notice for being in possession of a controlled substance.
At about 7.40pm the same day, police were conducting a driver testing station when they noticed a Ford sedan turn off quickly before entering the testing line.
Police found the driver had a disqualified licence from a previous drug driving offence and she allegedly returned a positive result to methamphetamine when tested.
She was reported for driving while not authorised and her car was impounded for 28 days.
On Tuesday, April 27, police stopped a silver Holden sedan being driven by a 45-year-old Port Pirie man for a mobile driver test.
The learner driver allegedly returned a positive drug test to cannabis.
He was issued with an $847 fine for drug driving and a further fine of $472 for breaching permit licence conditions with a licence suspension of three months.
About 1.45am on Wednesday, April 28, police stopped a silver Nissan sedan on Three Chain Road, Port Pirie for driver testing.
The 52-year-old Port Pirie woman was subjected to alcohol and drug testing, returning an alleged positive result to methamphetamine.
Police located an ice pipe on the rear passenger footwell and conducted a search of the vehicle where they located a knife, about half a gram of methamphetamine and a handheld taser disguised as a torch.
The woman was issued with an expiation fee for failing to produce her probationary licence immediately on request and for having an adult passenger in the vehicle who failed to wear a seatbelt.
The driver will also be summonsed to attend court at a later date.