A report into the access lobbyists have to parliamentarians has been slammed for failing to address the "secretive system" corroding trust in public institutions.
A Senate inquiry on Tuesday recommended the government hold a further review into the issue, despite finding lobbying regulations have not maintained pace with developments in the multi-billion dollar industry.
The report represented a missed opportunity for well-overdue improvements to the system, Independent Senator and committee member David Pocock said.
"Weak and ineffective regulation of lobbyists and a secretive system of allowing access to Parliament House undermines public trust in our parliamentary institutions," he said.
"The enormous weight of evidence tendered to this inquiry - including from current lobbyists - revealed the system as it currently stands is fatally flawed."
Senator Pocock released a dissenting report, calling for greater transparency of passes handed to lobbyists and an expansion and strengthening of the code of conduct.
Almost 1800 lobbyists have been issued security passes after being sponsored by an MP, allowing them to roam the corridors unaccompanied.
This gave them an advantage over other organisations or members of the public who wanted to influence politicians, opening the door to undue influence and corrupt behaviour, constitutional law expert Anne Twomey told the inquiry.
"Facilitating such opportunities is both unwise and inappropriate," she said.
But the committee found access to Parliament House should be facilitated, not hindered as it was in the interests of the democratic process that as many people as possible be given access.
The Greens joined Senator Pocock in calling for ministers to be required to regularly publish meeting diaries, so that the public has greater clarity on who decision-makers are meeting with.
Greens Senator Larissa Waters also said the cooling-off period before former ministers and senior staff could become lobbyists should be extended from 18 months to five years
"It's time to restore trust in our democracy by increasing transparency, shining a light on who is meeting who, and stopping the revolving door giving donors, former politicians and industry mates lucrative perks," she said.
