The Court of Criminal Appeal has increased from three to five years a prison sentence imposed on a company director for his role in insurance fraud schemes totalling some £324,000.

The court described the fraud as "calculated, deliberate and sophisticated".

The Director of Public Prosecutions (DPP) had sought an increased sentence for Michael Byrne, arguing the original three-year sentence imposed on him Dublin Circuit Criminal Court was "unduly lenient".

Byrne (40), of Prucklish, Newtownforbes, Co Longford, a director of Michael Byrne's Motors, was convicted by a jury of conspiring with others to defraud the PMPA by falsely pretending that a road accident had happened in 1994 at the M50 near Lucan, Co Dublin.

He also pleaded guilty to additional charges of falsely obtaining money from the PMPA and Cornhill Insurance companies from a further series of staged accidents and from falsely reporting that a car had been stolen. The offences occurred on dates from 1994 to 1996 at a number of locations.

The circuit court had imposed two six-year jail terms on two charges but suspended three years of those sentences in each case and also imposed three terms of four years, with the two final years suspended in each case, all to run concurrently.

Yesterday, allowing the appeal by the DPP, the Court of Criminal Appeal varied the sentences and substituted a five-year jail term to run from the date of sentence.

In the circuit court, the gardaí were complemented by the judge for their "exemplary work" in the case. The circuit court directed that €5,000 out of a sum of €50,000 that had been lodged in court on behalf of Byrne should be paid over to the Garda Benevolent Fund, with the balance being paid to the PMPA.

Giving the appeal court judgment, Mr Justice Murray, sitting with Mr Justice O'Sullivan and Mr Justice de Valera, said the offences were calculated, deliberate and sophisticated. They involved careful preparation of a plan that created the circumstances where it would be believed a road traffic accident had taken place, and that serious damage had been caused to particular vehicles and in some cases to individuals.

He added that Byrne was in the motor trade and had clearly used his own knowledge and expertise. He would have had access to crashed vehicles in the trade in order to mount the series of offences in which he engaged.

Having regard to the gravity of the offences and notwithstanding matters that had been put forward in mitigation of behalf of Byrne, the appeal court was satisfied that the sentences imposed in the circuit court were not only lenient but unduly lenient, Mr Justice Murray said.

The appeal court was taking into account a number of mitigating factors put forward on Byrne's behalf, including that he had, in effect, "lost everything". He had lost his business and his standing in the community. He had a previous good record with no previous convictions.

Some €50,000 had been contributed with the help of family as compensation. But for the various mitigating circumstances, the court would certainly have considered a more severe sentence than in fact it was imposing, the judge said.

Counsel for the DPP, Mr George Birmingham, had submitted that the offences had been carried out over a "not insignificant" period and that what had happened was not a once-off incident. Mr Gerard O'Brien representing Byrne, said it was accepted that he had not been in trouble previously and that there was no prospect of him re-offending.