In the mid 1990s, as the royal commission into the NSW police was in full swing, Labor MP Franca Arena stood up in NSW Parliament and threw an unforgettable bomb.

Arena felt the spotlight had to be shone on people in high places and she named retired Supreme Court judge David Yeldham and former state MP Frank Arkell as potential paedophiles.

Former Wollongong lord mayor Frank Arkell, who was murdered by Mark Valera. Credit:Robert Pearce

Both men denied her claims and Arena was condemned for relying on the cover of parliamentary privilege to protect her from being sued for defamation.

More than 20 years on, parliamentary privilege has again become a sinister term. This privilege is about parliamentary immunity. It exists so MPs can speak freely in Parliament without fear of prosecution or being sued for defamation. It is a critical part of our political system.