A US patrol officer stopped a car for suspicious driving and found to his surprise that a drunk mother had let her one-year-old son take the wheel, the Ohio state police department said.
Marya Green, 29, of Goshen Township, near Cincinnati, was arrested late on Tuesday and found to have a 0.11 per cent blood alcohol level - well above the 0.08 per cent legal limit, said the town's police department spokeswoman Mandy Storer.
Her licence already suspended for a previous drink-driving offence, Green had put her infant son behind the steering wheel, while two other children aged eight and five were also travelling in the car, she added.
"Let's be honest, a one-year-old child doesn't have the skill to drive a car. We all know that," Storer said.
"But he was riding, the hands were on the wheel. She was allowing him to steer."
It was Green's third drink-driving offence in six years, she said.