A Letterkenny man claimed he never received a summonse for not displaying tax and using a mobile phone while driving.
However, Charles McDonagh of 42 Balymacool Woods, admitted to both offences when he appeared at Letterkennny District Court.
Garda Inspector Michael Harrison told the court that McDonagh, 41, was stopped by Gardai on August 20th last.
He admitted both offences and apologised to Judge Paul Kelly.
Judge Kelly warned him that there were a lot of accidents being caused because of people driving while talking on phones.
Judge Kelly imposed a fine of €100 for non displayal of tax and ordered him to pay a €100 donation to the pro social drivers course.