'Infuriating': Aboriginal voters turned away, told to line up again on SA election day

Nicole Clinch says she was looking forward to voting in the Voice election, but faced difficulties at the Kilburn pre-poll centre. (ABC News: : Lincoln Rothall)

First Nations voters say they were forced to line up twice — or even turned away — when trying to vote in this year's Voice to Parliament election.

Documents obtained by the ABC show the Electoral Commission was aware more than a year before polling day that double queuing would be perceived as "discriminatory behaviour".

The revelations have prompted more criticism of the Electoral Commission, which is already subject to an independent review for its handling of the election.

When Nicole Clinch arrived at a Kilburn pre-poll centre on March 17, voting in South Australia's state election was not her first priority.

"As an Aboriginal person, you don't generally get a lot of opportunity to have your specific voice heard," said Ms Clinch, a Badimia Yamatji woman.

This year marked SA's second Voice to Parliament election for First Nations voters to elect 46 representatives across six regions.

The ballot was held simultaneously with the state election on March 21.

Thousands of First Nations South Australians are eligible to vote in two elections, in a potential historic first for the state.

Ms Clinch said she made it "very clear" to a polling official at the door that she wanted to cast a vote in the Voice ballot. She said she was directed to stand in the ordinary election queue with her partner, who is not Aboriginal.

"When I got to the lady who was ticking my name off on the screen, I also told her I needed to vote in the First Nations Voice election; she said, 'Yep, you just need to do this first and then go into the other line'."

After casting her state election ballot, Ms Clinch walked over to the declaration vote queue and waited in line another "five to 10 minutes" before asking for a Voice ballot.

SA's second Voice to Parliament election for First Nations voters coincided with the state election on March 21 this year. (ABC News: Che Chorley)

Ms Clinch said the staff member at the desk "didn't seem to know much about it [the Voice election] at all".

"He was looking at me and was very confused as to 'but if you've already voted, why are you trying to vote again?'," Ms Clinch recalled.

"And I'm like, 'well I actually haven't voted in the First Nations election — they're two different elections'.

Ms Clinch said the situation did not improve when the polling booth manager was called over and told her she should have been in the declaration line from the beginning.

"He's like, 'Look,