Since then the has been the only civil police force in the state now known as Ireland . Other police forces with limited powers are the Military Police within the Irish Defence Forces , the Airport Police Service , and Dublin Port and Dún Laoghaire Harbour police forces .
Since then the Garda has been the only police force in the state now known as the Republic of Ireland , with the exception of the Military Police within the Irish Defence Forces , the Airport Police , and Dublin Port and Dún Laoghaire Harbour police forces .