The regulation of lobbying in NSW remains "well below international best practice", the state's anti-corruption watchdog has heard, despite the body making several recommendations a decade ago following a previous inquiry.
A fresh Independent Commission Against Corruption probe into the regulation of how NSW public officials are lobbied, accessed and influenced began on Monday presided over by Peter Hall QC.
In his opening remarks, counsel assisting the commission Nicholas Chen SC said ICAC recommendations from 2010 regarding the registration of in-house lobbyists, the retention of information on lobbying efforts and the banning of gift-giving, were not heeded by state parliamentarians.
Those recommendations were made as part of ICAC's Operation Halifax which also probed the lobbying of public officials and authorities.
Other Halifax recommendations were either adopted or partly adopted.
"It's fair to say that the outcome has been somewhat piecemeal, and appreciably less than the lobbying scheme of the Commission recommended be developed and implemented," Dr Chen said.
"Registration is only required for third-party lobbyists, not in-house lobbyists, and there's next to no information specifically required to be kept and thus disclosed ... (and) there remains no prohibition on lobbyists offering gifts."
Dr Chen said lobbying at the federal level was a $1 billion-a-year industry in 2011 but, in NSW, it was regulated via a "minimalist" scheme that may inhibit adequate public scrutiny and transparency.
The 2010 probe identified three key corruption risks regarding lobbying: a lack of transparency; inadequate record-keeping; and the ability of powerful parties to access public officials.
Dr Chen said those risks remain.
It was important for the 2019 inquiry to discuss the "optics" of lobbying, he added, given declining trust in government.
"A criticism is that lobbying intersects with 'big business' and other powerful interest groups, and such entities covertly persuade government to the detriment of the broader public interest, and is thus undemocratic," Dr Chen said.
The Operation Eclipse inquiry will on Monday also hear from Professor AJ Brown of Transparency International and Dr Simon Longstaff from The Ethics Centre.
After Wednesday the inquiry will adjourn until October.