A former staffer to disgraced Labor party powerbroker Adem Somyurek is set to appear before a Victorian anti-corruption inquiry.

Adam Sullivan will give evidence at the Independent Broad-based Anti-corruption Commission inquiry into allegations of branch stacking by Labor MPs and their staff on Wednesday.

Mr Sullivan worked for Mr Somyurek and his allies in Labor’s moderate faction – federal member for Holt MP Anthony Byrne and state MP for Kororoit Marlene Kairouz.

Mr Byrne has admitted to paying for other people’s Labor Party memberships as part of a “well-entrenched” model of branch stacking led by Mr Somyurek.

The memberships helped the faction gain influence in Melbourne’s southeast and to ensure their preferred candidates were preselected.

The practice is not illegal but is against Labor Party rules.

IBAC is investigating whether public funds were used for such work.

Mr Somyurek’s former executive assistant Ellen Schreiber told the inquiry on Tuesday that she did factional work during office hours.

Ms Schrieber said she had not been asked to do so when she first joined the office in January 2019. However, between June and July of that year “80 per cent” of her time involved dealing with ALP memberships and factional work .

This included attending internal Labor Party meetings that approved party memberships, along with Mr Sullivan and another man named Oscar Goodwin.

The trio were responsible for assessing applications in Melbourne’s west, north and south-east.

Ms Schrieber left the office in August 2019 to work for Mr Byrne, who blew the whistle on Mr Somyurek’s behaviour.

Mr Byrne told the inquiry on Tuesday he was aware of branch stacking in other factions, including Premier Daniel Andrews’ socialist left in Melbourne’s south-east.

Mr Andrews said on Tuesday he had not attended factional meetings since he became Victorian Labor leader in 2010 and had always followed party rules.

-AAP