A corruption inquiry has heard former New South Wales Labor minister Eddie Obeid engaged in "lobbying of an unusual kind" when he was an MP.

Earlier this year the Independent Commission Against Corruption found Mr Obeid corrupt in relation to a mine licence in the Bylong Valley, but he described that inquiry as being "full of superficiality and bias".

A new inquiry that began today is investigating allegations that between 2000 and 2011 Mr Obeid misused his position as an MP to influence the issue of cafe leases at Circular Quay and failed to disclose a family interest in the leases.

Three leases were sold to an Obeid front company in 2003 , but the deal was not exposed until 2012.

The ABC revealed yesterday that despite this, the lease on the third cafe was renewed in late 2012 by the Sydney Harbour Foreshore Authority.

In his opening address today, counsel assisting Ian Temby said Mr Obeid tried to influence public officials for the financial benefit of himself and his family.

Mr Temby said the hearing is the culmination of three separate investigations involving the State Treasury, the Department of Water and Energy and NSW Maritime.

He said there is a clear distinction between a lobbyist and a member of parliament but Mr Obeid blurred the distinction.

Sorry, this video has expired New corruption inquiry begins into Obeid ( Karl Hoerr )

"A member of parliament is a trustee of the power vested in him or her by the people, acting in a fiduciary capacity to serve the public interest," Mr Temby said.

The ICAC has been told Mr Obeid lobbied Labor MPs Carl Scully, Eric Roozendaal, Michael Costa and Joe Tripodi over cafe leases and the leases were not put to a competitive tender process.

It heard that Mr Obeid deliberately did not tell the MPs about his family involvement in cafe leases at Circular Quay because he was lobbying for all lease holders and not just his family.

Mr Temby said he has no doubt the former ministers will emphasise in their evidence that they should have been told.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Listen Duration: 5 minutes 33 seconds 5 m Three more Obeid family businesses under ICAC spotlight ( Tim Palmer ) Download 2.5 MB

After the cafe licence inquiry the ICAC will look at allegations Mr Obeid tried to influence decisions favouring the company Direct Health Solutions and influence the issue of water licences on his farm Cherrydale Park.

Mr Temby said Sue Heaney, a public official who accepted redundancy after being disciplined as a result of Mr Obeid's lobbying over water licences, now works as a massage therapist.

The counsel assisting said the water licence tender process was "far from impregnable to abuse as procedures were notably lax".

There was laughter in the public gallery when Mr Temby noted that Mr Obeid's business associate Rocco Triulco will be a witness.

Mr Triulco was a colourful witness an at ICAC inquiry into the Obeid family earlier this year.

Retired judge Anthony Whealy is presiding over the inquiry.

Mr Tripodi and Mr Costa are on the witness list along with Mr Obeid's son Damian

Obeid's brother-in-law told of stress of running cafes

Mr Obeid's brother-in-law John Abood fronted the inquiry today.

He told the inquiry the stress of running three cafes for the family almost gave him a nervous breakdown and he had swollen ankles and could hardly walk.

Mr Abood said he ran the cafes for the family but was "not a frontman" for the Obeids.

He added that it was fair the cafe licences were renewed without a tender.

Mr Obeid, who recently turned 70, has stated that nothing will come of the new inquiry.

But Mr Temby has told the inquiry Eddie Obeid could have committed a criminal offence, misconduct in public office.

Despite being referred to the Director of Public Prosecutions, the NSW Crime Commission and the Australian Tax Office over the previous ICAC findings, Mr Obeid maintains he has done nothing wrong and is the victim of a "political witch hunt".

The last inquiry saw two public galleries full, but today the ICAC is only opening one.