Internal ABC report reveals the National broadcaster spent most of the time speaking to Yes campaigners ahead of Voice referendum - before majority of the country voted No

An internal ABC review has found its coverage of the Voice referendum was dominated by Yes supporters. 

The national broadcaster's 2023 Voice to Parliament Referendum report found that 51 per cent of voices appearing on the ABC during its referendum coverage were in favour of a Yes vote. 

In contrast, just 23 per cent of speakers platformed by the ABC were in favour of a No vote, while the rest were neutral or undecided, The Australian reported. 

More than 60 per cent of Australians backed the No campaign on the October 14 plebiscite, while just shy of 40 per cent voted Yes. 

The report, compiled by editorial policies manager Mark Maley and published on Monday, revealed that the ABC received 383 complaints about its referendum coverage - with over 80 per cent relating to claims of bias or a lack of balance. 

Only 121 complaints were investigated and just four were upheld. 

It is unclear what those complaints were. 

The report also said that balance was not needed. 

'Teams were explicitly told that 50/50 balance of advocates was not required,' Mr Maley said. 

'The goal was to ensure that audiences on all platforms were presented with the main arguments for and against the propositions in the referendum on every platform within a reasonable time.

'This was achieved.'

The report praised Radio National's breakfast show, led by Q+A stand-in host Patricia Karvelas, for its 'influential role in the media coverage'.

'Stand out interviews included: Jacinta Nampijinpa Price, Noel Pearson, Marcia Langton, Tony Abbott and Anthony Albanese, Mr Maley said in report.

The review also said RN's coverage including on programs Late Night Live and Between the Lines 'sought a diversity of perspectives'.

The latter is presented by academic and respected news editor Tom Switzer, who is often described as one of the ABC's few conservative voices.

He recently announced he is leaving the ABC, with one insider suggesting Switzer had been 'ruffling feathers' with his choice of guests. 

The report also touched on the issues the ABC had with covering the Garma Festival in northeast Arnhem Land in August celebrating indigenous culture. 

'Indigenous and planning teams knew it was going to predominantly feature Yes perspectives so they tried hard to include other voices,' the report said.

Prominent No campaigner Warren Mundine pulled out of a special Q+A episode filmed in Garma fronted by Insiders host David Speers. 

At the time, the ABC was forced to issue an embarrassing clarification after the Garma show aired false claims the official 'No' campaign was using  'AI-generated aboriginals' in their advertisements.