The State's financial watchdog has revealed that up to a fifth of motorists avoided penalty points because their cases were not pursued for various reasons.

The Comptroller and Auditor General report found significant weaknesses in aspects of the operation of the fixed charge notice system.

The report examined garda databases of fixed charge notices issued in 2011 and 2012.

In the two years, almost 850,000 road traffic offences resulted in the issuing of fixed charge notices.

The examination indicated around 11% of all recorded fixed charge notice cases end up unpaid and without being answered in court.

Court proceedings could not be taken in over 3,000 notice offences detected in 2011 and 2012, because they were not initiated within six months of the date of the offence and became statute barred.

A significant number of the 3,000 notices that became statute barred was due to the late entry of data on to the system.

One in nine detected fixed charge notice offences was unpaid but did not result in a court hearing because the summons was not served by gardaí.

Notices for penalty points were issued to drivers of company cars for over 20,000 road traffic offences in 2011 and 2012, but just 28% of these were paid.

The report found 49% of these were not pursued and were given "company summons" status on the system.

Penalty points cannot be attached to a company.

The report estimated that €1.12m was foregone in revenue in 2011 and 2012 in respect of company car cases terminated or not pursued.

The report found that circumstances accepted as grounds for termination of a fixed charge notice for speeding included a driver who was late for a swimming lesson.

Other examples of circumstances accepted included a driver who was speeding because they were late for a religious ceremony and another case where a person was rushing to pick up a relative from a bus station.

Comptroller and Auditor General Seamus McCarthy said there were no controls in the system to restrict garda members with a facility to terminate penalty points from doing so in cases outside their authority.

He also outlined a litany of other incidents where public money had been wasted during 2012.

Welfare payments of €97m incorrectly allocated

The report also shows there were €97m of welfare overpayments by the Department of Social Protection last year.

Fraud was responsible for 40% of recorded over-payments.

A further 37% of them arose from client error.

Just over €54m of the money was recovered by the department in 2012.

€3.3m spent on abandoned pathology office

The report found the State has incurred a cost of €3.3 million in relation to an abandoned building project for the construction of a new State Pathology Office and Dublin Coroner's facilities.

The project was hit by delays relating to planning, procurement, and the building contractor going into receivership. It was ultimately abandoned.

Work had started on a site owned by Dublin City Council in Marino, where the services are currently located in prefabricated accommodation, in July 2010.

The building contractor went into receivership in November 2010, leaving a partially completed structure.

The partially completed structure has now been demolished. A suitable site is being considered for a scaled down "medico-legal centre".

The C&AG also noted that the Government deficit, the gap between income and spending, fell substantially between 2011 and 2012, mostly because of reduced spending on bank stabilisation.

However, the general Government debt continued to rise - increasing by 14% in 2012, to close the year at €192bn.