The State competition watchdog has defended taking four years to probe insurers over accusations they are engaged in anti-competitive practices.
The Competition and Consumer Protection Commission (CCPC) also denied it is ineffective.
It launched an investigation in 2016 into claims that motor insurers and brokers were engaged in anti-competitive practices by openly signalling premium price rises.
Asked why the probe is taking so long, a spokesperson for the CCPC said there were no further updates at present.
It has said in the past that it was at an "advanced stage" in its probe of insurers.
Asked if it was ineffective, the spokesperson said: "The CCPC is not ineffective. This is a legal process and we are required to undertake a thorough investigation.
"There are multiple parties, which makes it particularly lengthy. But since you last enquired significant progress has been made. Once we are in a position to, we will make a public statement.
"Finally, we think that it is unfair to question our competence. The CCPC, like any other statutory body, has to work within a legal framework and we are working to achieve this as quickly as we can."
Peter Boland, of the Alliance for Insurance Reform, said his organisation had lost faith in the probe process.
"We were told in February 2019 that this investigation was 'in its latter stage' and we have still not seen the report. We have lost faith in the process at this stage," he said.
Motor insurers came in for sustained criticism after a Central Bank report before Christmas showed that the cost of claims fell between 2009 and 2018. This was during a period when premiums rose by 42pc. Average premiums were just over €700, some €265 more than in 2009. Over the same period, the cost of claims per policy fell by 2.5pc.
The report also found that the legal bill for motor claims settled in the courts between 2015 and 2018 amounted to just under €500m.
The findings on the fall in the cost of claims cast doubt on repeated industry statements that higher premiums are the result of spiralling payouts and increased claims. In May last year the European Commission launched a formal probe into claims of an insurance cartel operating here.