The Law Society has warned that the proposed closure of four courthouses in Dublin will lead to the collapse of criminal trials because of absent witnesses.
The Courts Service is undertaking a period of consultation ahead of the proposed closure of Swords, Dún Laoghaire, Balbriggan and Tallaght courthouses.
Local courts are closing across Ireland at a rate of more than 12 per year.
The Courts Service is now proposing leaving the capital with only two court venues - the Criminal Courts of Justice in Dublin 8 and Blanchardstown Courthouse.
The Law Society said the proposals represent a short-sighted and flawed policy.
The society, which represents solicitors, said some witnesses - particularly in more minor criminal trials - will not travel to give evidence and cases will not proceed.
The courts service warned that pressure on courtroom availability will be further increased by the introduction of a Court of Appeal and without changes to the structure of courts, services will be cut.