GARDA Commissioner Martin Callinan has rejected suggestions that a culture of non-enforcement of penalty points is being tolerated by his force.
The commissioner spoke out amid allegations that gardai have cancelled a large number of penalty points.
It has been alleged by a garda whistleblower that tens of thousands of penalty points have been terminated for motorists around the country.
The Irish Independent revealed last week how at least two judges, a leading rugby player and a television presenter were among those who had penalty points written off.
A number of TDs made efforts to name the people involved in the Dail earlier this week, but were blocked from doing so.
In a statement, Mr Callinan said that the internal probe into the claims – to be carried out by Assistant Garda Commissioner John O'Mahony – would be "comprehensive and rigorous, whatever the circumstances behind them".
"There is no question of what has been described as a culture of non-enforcement of penalties being tolerated by An Garda Siochana," he said.
"The public can be assured that the investigation into the allegations will be comprehensive and rigorous, whatever the circumstances behind them," he added.
Garda superintendents have the power to adjudicate on and cancel penalty points.
They can also intervene if written to by a motorist who wishes to appeal.
The commissioner said people should not make assumptions about the cancellation of traffic penalty points without being aware of the full facts.
Mr Callinan said he was limited in what he could say publicly about the issue until the examination was completed.
Mr Callinan said he was determined that the commitment of the force to the effective enforcement of road traffic legislation would be absolute.
He pointed out that effective enforcement by members of the force, along with the efforts of others, had contributed to a dramatic decline in the number of road deaths and injuries.
His view is backed up the latest figures showing that the number of road deaths so far this year is down by 14 on the corresponding period last year.
Dublin is now regarded as the safest capital city in Europe on the roads.
Mr Callinan said the effective enforcement was evidenced by the fact that every year hundreds of thousands of penalties were imposed and enforced for breaches of road traffic legislation.