A 78-year-old man was among 12 drivers caught behind the wheel in Tayside last week while unfit through drink or drugs.
The pensioner was stopped by officers after he was seen driving his car with the lights off. He was allegedly twice the legal alcohol limit.
In a separate case, a 20-year-old man from Perth, who was involved in a road smash, was found to be three times the legal limit, police said.
A senior officer said he was concerned about some of the high breathalyser readings registered during the third week of the festive road safety operation.
Chief Inspector Sandy Bowman, head of road policing, said, “Some of these drivers have been detected with high readings so that they must have known that they would be well over the limit.
“Despite this they have taken a conscious decision to get behind the wheel of a car.
“To most people that is utterly incomprehensible and this is borne out by the fact that we continue to receive reports from concerned members of the public regarding such irresponsible behaviour.”
Five of the 12 offenders were snared directly as a result of calls to the police.
Mr Bowman said, “While these drivers appear to have a total disregard for their own or other people’s safety, thankfully others do share our concerns and by working together we can remove them from the road.
“I would re-emphasise that we all have a part to play in making the roads safe for ourselves and our families and I encourage the public to continue with the level of support they have provided so far.”
In one incident, motorists concerned about a man’s driving alerted police, resulting in a 40-year-old being found twice the legal limit.
Of the arrested drink-drivers, 11 were men, and half of them were under the age of 25.
Mr Bowman said, “It is evident that the drivers we have detected were prepared to take the risk, probably thinking the chances of being caught were slim.
“They have found out to their cost that they were very, very wrong and will now have to deal with all that a drink/drug-driving conviction means.”
In addition, 49 drivers and seven passengers were caught committing seatbelt offences, while officers found one child not properly restrained.
Some 52 drivers were reported for using a mobile phone at the wheel, while four vehicles were seized because of insurance or other document offences.