A new report has recommended a Commission of Inquiry into media ownership in Ireland.
The report was commissioned by Sinn Féin MEP Lynn Boylan and carried out by two independent legal firms.
It raises concerns about the extent of media ownership by businessman Denis O'Brien.
It also recommends that a Commission of Inquiry looks at the role of RTÉ as a public service broadcaster, as well as what it described as the "chilling effect" of current defamation laws.
"Politicians seem to balk at the thought of effectively dealing with the issue," said Ms Boylan at the launch of the report in Dublin today.
Sinn Féin's @LNBDublin getting ready to launch report on the concentration of media ownership in Ireland. pic.twitter.com/Tu70jqZW4H
— Sinn Féin (@sinnfeinireland) October 24, 2016
She added: "An open and diverse media is crucial to the health of any democracy.
"We need a media that holds those in powerful positions to account, one that seeks the truth and ensures that the public has access to the truth."
Conclusions & recommendations from @LNBDublin commissioned report into the concentration of ownership in Ireland's media market. pic.twitter.com/5c9c5chG1A
— Sinn Féin (@sinnfeinireland) October 24, 2016