The Magistrate’s Court heard that a member of the public spotted a grey Peugeot 306 being driven erratically in St Helier and followed the car from outside of the Pomme d’Or Hotel to First Tower and up toward West Hill.
The States police stopped the car near Haute Vallée School and the driver, Theresa Porter (53), of Clos Le Gallais, gave a positive breath sample.
At Police headquarters, Porter again gave a single sample, which showed a level of 113 micrograms in 100 millilitres of breath. The legal limit is 35 mcg.
Advocate Adam Harrison, defending, said that Porter has been driving for 20 years and this was the first incident of any kind that she had been involved in. He added that she had asked him to apologise to the court on her behalf.
In sentencing, the Assistant Magistrate Peter Harris said: ‘On this occasion I accept you made a mistake but please make sure you don’t repeat that mistake.’