Animal rights activists say a High Court rejection of their challenge against surveillance laws in NSW prevents necessary exposure of the industry's animal cruelty.
A majority of four justices against three found the Surveillance Devices Act did not unfairly burden freedom of political communication in a judgment on Wednesday.
"The provisions had a legitimate purpose of the protection of privacy," they wrote in a summary of the decision.
Justice James Edelman concluded that evidence submitted of farming practices recorded covertly revealed "shocking cruelty" towards animals.
But the case "was presented on the basis that the activities, albeit undeniably cruel, were not established to be unlawful."
The Farm Transparency Project took the state government to court in June 2021, stating that police had increasingly used the Act to limit public awareness of large-scale harm and cruelty towards livestock.
The not-for-profit group's director Chris Delforce said "ag-gag" laws prevented consumers from seeing day-to-day, legal and industry-standard cruelty they were complicit in funding, he told AAP.
"Many people would not support it if they were made aware," he said.
He said the disappointing decision had broader implications preventing NSW media outlets from publishing any public interest material gathered via trespass.
Mr Delforce said he faced prosecution after publishing video footage of "lawful cruelty in numerous piggeries and the country's largest pig slaughterhouse".
His trial was dropped in 2017 on a technicality, but Mr Delforce said he was already preparing to take the matter up to the High Court.
He had obtained the recordings through trespass contrary to the law, and argued sections of the Act impermissibly burdened the ability to publish the information.
The High Court concluded the Act did not unfairly restrict freedom of communication or publication by a person in recording or reporting lawful activity where they are "complicit in obtaining the information exclusively in breach of the law".
Similar surveillance laws exist in most other Australian states that achieve the same level of privacy but give clear exemptions for public interest material.
However, the High Court found the statutory schemes of other Australian jurisdictions were not obvious and compelling alternatives.
"They did not pursue the same purpose and were broader in application."
Justice Stephen Gageler agreed the Act prevented the publication of activity of concern, and infringed on the constitutional guarantee of freedom of political communication.
"Conformity with the constitutional guarantee means that privacy cannot always trump political communication," he wrote in his dissenting judgment.
In contrast Justice Edelman found the best protection for animals against cruelty in a democracy was not the implied freedom of political communication.
"The best protection for non-human animals must come from parliament," he wrote, adding that the laws included powers for inspectors to enter land without consent if reasonably suspicious that cruelty had occurred.
The maximum penalty for breaking the law is five years in prison.
Mr Delforce's charity agitates for political and legal changes to animal agricultural practices and animal welfare standards with the objective of ending modern farming and slaughtering practices.
And the High Court decision was not going to change that, he said.
"The industry does not have a right to keep its horrific practices secret and we are going to continue publishing material.
"We accept that may open us up to criminal prosecution."
He believed if a larger media organisation took on the case they would have a better chance of winning.
Australian Associated Press