The 38-year-old woman, who was sitting in the passenger seat, was meant to be supervising her daughter, who was practising for her driving test in the Upper Austrian town of Steyr. But when asked to take a breathalyzer test by police she was found to have a blood alcohol level of 0.96 per mille.
The woman's husband, who was sitting in the back seat, was also over the legal limit - and police had to call a sober member of the family to come and pick them up and drive them home.
Austria has an alcohol limit for drivers of 0.5 per mille. Novice drivers and anyone accompanying a learner driver should not have over 0.1 per mille.
Police stopped the family at around 6pm, as part of a routine check on the B122 outside Steyr. The driver's mother was visibly drunk and so police asked her to take a breathalyzer test.
The 18-year-old girl had not been drinking, but she had no license and so should have been accompanied by a sober, licensed driver. The mother has been told she may no longer take her daughter on practise drives and she could receive a fine of up to €5,000.
ÖAMTC lawyer Corinna Hotz said anyone accompanying a novice driver must be responsible for checking that their ‘student' respects road laws and should be ready to take the wheel if necessary.