At least $26 million of taxpayers' money went to advertising, consultants, taskforces and legal fees trying to win over the public on the NSW Government's ill-fated greyhound racing ban and forced council merger policies.

Documents obtained by the ABC under freedom of information laws show the Department of Premier and Cabinet spent $4.7 million on legal fees and "other costs" as it fought through the courts to forcibly merge resistant councils.

An email chain between the Crown Solicitor's Office and the Premier's Department shows that the legal bill had already grown to $1.6 million by March 2017, months before Woollahra Council won leave to appeal against the forced mergers in the High Court.

In addition, almost $6 million was spent on advertising campaigns to spruik the benefits of council amalgamations and the greyhound racing ban.

The advertising campaigns have today been criticised in a report by the Auditor-General Margaret Crawford for not representing good value for money and being inconsistent with guidelines that require government advertising to be objective.

"We did identify shortcomings in both campaigns that potentially compromised value for money," Ms Crawford states in the report.

"These mostly resulted from the perceived urgency to advertise.

"Some advertisements used subjective or emotive language ... which we consider inconsistent with the requirement of 'objective presentation' as set out in the guidelines [on government advertising]."

Taxpayers deserve better: Opposition

The Auditor-General found that in the "Dogs Deserve Better" greyhound racing ban campaign two statements presented as fact were inaccurate.

She also found during the first few days of the campaign, ads broadcast on radio did not clearly identify that they had been authorised by the NSW Government.

State Opposition Leader Luke Foley leapt on the report and said the ads were clearly a waste of money.

"These were dud policies from the beginning and taxpayer money shouldn't have been wasted trying to sell them," Mr Foley said.

The documents obtained by the ABC show the Government spent at least $6.4 million on the greyhound racing ban policy, including:

More than $4.5 million on the Special Commission of Inquiry that recommended the now abandoned greyhound racing ban policy; and

More than $4.5 million on the Special Commission of Inquiry that recommended the now abandoned greyhound racing ban policy; and $1.8 million on the Greyhound Transition Taskforce that was set up to help the industry shut down, including a $1.5 million advertising campaign.

Those figures do not include the $41 million the Government is now spending to reform the industry after it overturned the racing ban.

The documents also show the Department of Premier and Cabinet spent about $15.5 million on other costs associated with the partially abandoned policy, including nearly $8 million on staff costs and almost $3 million on consultants' fees.

A department spokesperson said the four recommendations made by the Auditor General in the performance audit had been accepted and that Department would work with other government agencies towards their implementation.