Fine Gael has claimed there has been a dramatic increase in serious crime in the Dublin area.
The party has collated official figures for Dublin which it said showed that serious assaults have trebled between 2000 and 2004.
It also claimed that overall headline offences rose by nearly a quarter during the same period.
The Department of Justice has questioned the interpretation and presentation of the figures, and said that recent statistics showed that headline crime figures in Dublin fell by 4 per cent in 2003, and a further 4 per cent last year.
This compares with the figures collated by Fine Gael from parliamentary replies from the Department of Justice that there were 38,704 headline offences in 2000, which rose by 23 per cent to 46,787 in 2004.
Serious assaults rose 166 per cent, or up from 12 per week to 33 per week in the same period.
Detection rates also fell from 37 per cent in 2000 to 32 per cent in 2004.
The figures, which were broken down by station and division, showed that Blanchardstown, Coolock and Tallaght were the areas which experienced the highest increases, with the rate of headline offences having doubled in Blanchardstown.
Yesterday, Fine Gael finance spokesman Richard Bruton said the figures underscored the party's assertion that crime levels were a serious concern and were not being properly addressed.
"Some commentators have suggested that Fine Gael's vigorous campaign on crime is just political hype," he said.
"Even a casual glance at the crime statistics in Dublin explodes that argument. There is no doubt that there are huge questions to be asked about Government policy, about Garda strength, and the effectiveness of Garda deployment."
A spokesman for the Department of Justice said the figures failed to take into account a number of factors.
The year 2000 was one of the lowest on record, while the figures failed to take into account the growth in population in the greater Dublin area.
There was also a change in the way crime statistics were collected after the introduction of the Pulse computer system.
He said the actual rate of headline offences, measured as a percentage of the population, had fallen by 14 per cent between 1995 and this year.
There had been a continuous decline in crime levels for the last nine quarters.