Almost four out of 10 rape and sex offence cases brought before the criminal courts last year did not secure a conviction, figures show.
A total of 83 suspected sex offenders were charged in 2012 – a 32% jump in two years – with 21 acquitted and 12 nolle prosequi entered.
The Court Service said domestic violence cases also soared by 20% as new laws allowed same-sex couples, co-habiting partners and former couples with a child to apply for protection.
Some 12,655 men and women sought a safety, protection or barring order, with 230 people jailed or handed suspended sentences for breaching the orders.
Elsewhere 41 murder cases were heard in the Central Criminal Court, with 35 convictions for murder, manslaughter or attempted murder.
But the Court service said there was a significant decrease in high visibility, high nuisance and highly dangerous activity, including a record 41% fall in drink-driving cases over two years.
Almost 160,000 defendants accused of 384,231 offences came before the courts, resulting in 693 criminal trials.
The Chief Justice, Ms Susan Denham, said there was a general 14% reduction in more minor criminal matters on 2011.
“Specifically there was a 10% drop in more minor drug offences, a 22% drop in public order and less serious assaults, and a one third drop in drink-driving orders,” she said.
“There was also a 30% reduction in juvenile crime.
“We might well stop and wonder why there was such a drop in these high visibility and high nuisance criminal activities.
“Is this related to the effects of greater emigration or a lessened population?
“Are intervention and awareness programmes working?
“Are the sanctions of the courts taking effect?
“Whatever the answers to the above, they show that our courts mirror an ever-changing society.”
Justice Minister Alan Shatter said the drop in numbers before the court, and falls recorded in recent crime figures, was down to smart policing initiatives despite having a smaller force.
“This is now a safer country than it was two and a half years ago,” he said.
Garda Commissioner Martin Callinan said fighting crime remains a constant battle for gardai and warned the theft of mobile phones and cash remains a concern, particularly in city centres.
But he commended officers involved in the significant explosives and arms find in Santry last week.
“This is down to intelligence-led policing by very dedicated specialist units who are committed to making this country safer here in the south, and making the country as a whole safer for our colleagues in Northern Ireland who of course always balanced that nexus logistical support here and active service units operating in Northern Ireland,” he added.
Elsewhere, Fianna Fáil claimed there are genuine concerns that latest crime figures, showing a decrease in most recorded crimes, do not ring true and called on the Garda Commissioner to appear before the Oireachtas Committee on Justice
Niall Collins, the party’s justice spokesman, said: “The reality is that we still have a very serious problem with burglaries, muggings, drugs and violent crime in many parts of the country.
“People are struggling to see the evidence of the significant reduction in crime that Minister Shatter rushed to welcome last week.”