Officers have focussed on the issue over the last two weeks
Sixteen arrests have been made in relation to drink or drug driving during the Manx Grand Prix and Classic TT period.
The Island's police say the roads have been busier during the racing fortnight.
The Isle of Man Constabulary says it's an issue officers have been focussing on throughout.
Inspector Elliot Butler says there'll be further analysis to determine the split between locals and visitors:
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