A new report into the penalty points system has found that around one-in-six cancellations should be subject to further investigation.
The report from the Garda Professional Standards Unit, published this afternoon, recommends a series of legal changes so that Gardaí have more time to investigate potential offences.
The unit conducted a review of more than 600 files, and found that a sixth of them needed to be investigated further.
It has also recommended that people should not be able to apply for an NCT without having paid the fines for any fixed-charge notices.
Justice minister Frances Fitzgerald has appointed Judge Matthew Deery to become a new independent authority with responsibility for overseeing the system.