FANS travelling to and from this weekend's All-Ireland football finals should contact gardai if they suspect other motorists are drinking and driving.
He said people should use public transport where possible, but if driving should make sure that everybody in the car was wearing a seatbelt.
His comments came as the number of people killed on Irish roads stands at 137, up 16 on the same period last year.
So far this month, nine people have been killed.
"This Sunday, fans will be travelling to Croke Park, many by car, from Mayo, Dublin and Tyrone to attend the minor and senior football finals," he said.
"We want everyone to enjoy the day and don't want to see the trip to Croke Park to turn into a tragedy for anyone.
"If you encounter dangerous driver behaviour on your journey or are aware of anyone driving having taken drugs or of a drink driver, please contact An Garda Siochana. Your call may well save a life."
The garda traffic watch number is at 1890 205 805. Gardai have also have developed a traffic management plan for the event, with further information at www.garda.ie.