The European Commission has been called on to expand the scope of its probe into insurance firms here.
The commission is already investigating motor insurers over whether Insurance Ireland is operating a cartel by restricting access to a key database on the motor market.
The Alliance for Insurance Reform wants its investigation to now include liability insurance.
The call comes after a study on the public liability insurance market by the Competition and Consumer Protection Commission (CCPC) found a lack of data on the market was serving as a barrier to new entrants.
The CCPC said that the Insurance Link database, which is under the control of Insurance Ireland for data protection purposes, should be available to all insurers in the market and managed by an independent body.