It held that the objectives did not have to be generally accepted and could be "controversial", and ordered the Charities Board to reconsider Greenpeace's application for registration.
A Greenpeace spokesman said today that Greenpeace was about to resubmit its application "in the next few days".
High Court Justice David Collins has now ordered the board to reconsider Family First's case too. He said Family First would still need to show that its role was "of benefit to the public" by analogy to other cases, but he warned against applying that test too narrowly by comparing Family First only with existing charities.
"It is essential that the Charities Board not undertake its analogical assessment by seeking to carefully match Family First's purposes with organisations that have achieved recognition as charitable entities. Doing so would risk undermining the Supreme Court's recognition, for the first time, that political purposes are not excluded from being classified as charitable," he said.
"...I am saying, however, that the analogical analysis which the Charities Board must undertake should be informed by examining whether Family First's activities are objectively directed at promoting the moral improvement of society.
"This exercise should not be conflated with a subjective assessment of the merits of Family First's views. Members of the Charities Board may personally disagree with the views of Family First, but at the same time recognise that there is a legitimate analogy between its role and those organisations that have been recognised as charities. Such an approach would be consistent with the obligation on members of the Charities Board to act with honesty, integrity and in good faith."
Ms Barker praised the judgment as restating Voltaire's famous saying that, "I may not agree with what you say but I'll defend to the death your right to say it".
"Deregistration as a charity effectively can kill a charity, so it's not respecting your right to freedom of expression if you are going to be deregistered," she said.
The judgment would be a huge relief for all charities which currently feared speaking out on public issues because they might be deregistered, she said.
"Every charity that might come across an issue that needs governmental action, that needs legislative action, that needs something to happen, every charity that wants to engage with the democratic process, had previously been scared that by speaking out it was going to be deregistered," she said.
"The Supreme Court has made it clear that that should not be the case, but it's not clear that the Charities Registration Board is applying it that way."
The Family First judgment is online here.