The closure of 95 garda stations will be carried out to meet today's policing needs, and not because of the tightening of public purse strings, it has been claimed.
Justice Minister Alan Shatter defended his decision, which he claimed will improve the quality of policing in communities and not deprive them of resources.
He said that garda stations manned for a couple of hours a day do not act as a deterrent to burglars, adding that the spike in crime in 2011 was before any closures.
"Clearly you can't operate on the basis of a garda station network designed by the British Government, somewhere between 1850 and 1900, for the policing of the rebellious Irish, which was the perception of the location of some of these stations," he said.
Mr Shatter hit out at critics who said the closures will save only small amounts of money.
He added: "I am afraid that completely misses the point. The objective is to maximise the time that our well-trained and highly-skilled gardai spend on operational duties. This means increasing garda visibility, improving garda mobility and using limited resources better."
The mainly rural stations shutting on Thursday include 10 across Co Galway, nine in Co Kerry and in the district of Sligo/Leitrim, eight in Co Clare and four stations in Co Donegal, where several elderly people have been burgled and assaulted in recent weeks.
Another five stations will also close in the coming months under plans approved by the minister, on top of 39 closed last year. Some 28 garda districts are to be amalgamated to form 14. Protests are being held at several stations nationwide, including at Stepaside, south Dublin, and in Longford.
The priest who celebrated the funeral of murdered Detective Adrian Donohoe, Father Michael Cusack, publicly called for the Government to reflect on the huge cuts affecting the Garda force.
Mr Shatter said the Republic of Ireland's 4.5 million population will still have 564 stations, compared to 83 in Northern Ireland for 1.4 million residents and 340 stations in Scotland for 5.2 million people.