Conor Brady says the commission's remit was constrained "in so many ways"
A former Garda Ombudsman commissioner has suggested if An Garda Síochána were a private business, it would be shut down.
Conor Brady was head of the Garda Síochána Ombudsman Commission (GSOC) from 2005 to 2011.
His comments come after former Commissioner Noirin O'Sullivan announced her decision to retire earlier this month.
She said her job had become an "unending cycle of requests, questions, instructions and public hearings" - insisting this was affecting her ability to reform the force.
The Policing Authority has started consideration on the process to identify and appoint the next commissioner.
Mr Brady told Pat Kenny here on Newstalk: "If the Garda Síochana - if it was a chain of hotels or an airline - you probably would shut it down and start all over again.
"You can't really stand down a police force - but I honestly think that we're at the stage now where something on the scale of what was done with Patten (Independent Commission on Policing) in the North is probably necessary.
"It's very clear that the problem isn't just a commissioner".
"The policing structure is the police do the policing, there's one body to examine complaints - that's GSOC - there's an Authority which is effectively the board of directors and then there's the Inspectorate which is advisory.
"You'd have exactly the same in Northern Ireland or in, for the sake of argument, Yorkshire.
"The big difference is that although we've brought these bodies into existence here, we have so surrounded them with ambiguities and we have weakened their remit.
"We have given the appearance of oversight and change, while at the same time final authority has been brought back to the Department of Justice and the Government".
"Many of these institutions that we're talking about: you could argue that they're being set up to fail.
"For example: GSOC when it was set up was supposed to be the equivalent of the Northern Ireland Police Ombudsman... but in so many ways our remit was constrained.
"We couldn't investigate the commissioner, we couldn't investigate garda practice or procedure, we couldn't investigate anything to do with State security or intelligence... apart altogether from the fact that we were drastically under-resourced".
Mr Brady suggested a clear-out could benefit the force: "There are wonderful people in the guards - there are lots and lots of really good people at all levels in the guards - but it is clearly the case that there's a significant number who are not suited to the job, who don't like being in there and they should be given the option of doing something else".
"The body language is very clear: I was driving in this morning and passed a guard on special post at a certain building - I won't say where it was - but the very attitude, the hands thrust in the pockets, chewing gum, backside up against the wall, not making eye contact with the traffic passing by, clearly just putting in the hours.
"You see too much of that".
He also accused the gardaí of using their national security role as a 'get out of jail card' to 'tell people nothing'.
"The other big question here that has to be addressed... is this question of the dual role of civil policing and security.
"They're the only police force in Europe that have that - and what it enables the guards to do, and it has done this historically, is it enables them to cite State security, to pull down the shutters when there's any inquiry.
"It's a complete 'get out of jail' card that they have".