NSW Labor will seek to relinquish responsibility for its own internal elections to an independent body after suspected rorting during the national ballot that elevated Bill Shorten to the party's leadership.

But both factions at the party's NSW head office say the potential rort did not affect the outcome of the 2013 ballot that elected Mr Shorten, who hails from the party's right wing.

The party's NSW general secretary Jamie Clements said on Friday he would write to the NSW Electoral Commission for advice on whether that body could administer ballots for future state Labor leaders.

It follows concern raised by two senior Labor officials – John Graham, the NSW branch's left-wing assistant general secretary, and Australian Manufacturing Workers Union state secretary Tim Ayres, who is also on the national executive.

They had been pushing for a thorough investigation after revelations that the addresses for scores of voting papers for the national ballot between Mr Shorten and Anthony Albanese were altered by NSW Labor head office. It is understood that addresses for 73 ballots in the seat of Auburn were changed. About 40,000 ballots were cast.

The changes were made at the request of a then-staff member of Labor senator Sam Dastyari, who is a senior member of the party's right faction. A number of ballot papers were diverted to Hicham Zraika, an Auburn councillor who was accused of unrelated branch stacking offences and has been suspended from the ALP for six months.

In a statement, Mr Clements, who is from the party's right wing, said an internal review earlier this year had not uncovered any evidence suggesting Mr Shorten's election as leader was "flawed".

But he described the change of addresses as "serious" and will write to the NSW Electoral Commission to seek advice on the cost and capacity of that body administering future state leader ballots.

He said the party would adopt more robust measures for future changes to member addresses, ensuring they are "beyond the manipulation of any individual".

The left-wing assistant secretary would also be granted equal access to the NSW branch membership system.

Mr Graham said the address changes in Auburn were "an isolated but a serious incident", but could not have changed the result of the national ballot.

Mr Ayres welcomed the changes as "a very significant step forward", and agreed the national leadership ballot result was "beyond doubt".