Four Independent TDs have interrupted Dáil business to raise claims that tens of thousands of penalty points have been 'written-off'.
The Department of Justice says an investigation is underway after it was claimed 100,000 penalty point notices were quashed without any justification.
The Garda Commissioner has appointed an assistant commissioner to look into claims members of the force are involved.
In the Dáil, Deputies Mick Wallace, Clare Daly, Joan Collins and Luke 'Ming' Flanagan tried to raise the issue on Environment questions.
"Sorry Ceann Comhairle but this is a matter of the national interest, we've honest gardaí out there who are being victimised because they have uncovered the systematic abuse of motoring charges, terminations, to some very powerful and influential people in this State," said Deputy Daly.
Deputy Wallace later said: "We are being blocked from discussing it here a public inquiry is needed."
Deputy Collins called it a 'national crisis', while Deputy Flanagan said that it is time the country protected whistleblowers.