A sexual abuse help group says the judge got it wrong when he ruled in favour of a man who posted photos of his half naked wife on Facebook.
The judge dismissed the charge against the man who was accused of causing harm to his wife under the new Harmful Digital Communications Act.
The police are appealing the decision.
The man appeared in the Manukau District Court last September after he posted pictures on Facebook of his wife lying in bed in her underwear.
The couple had separated, the court heard, and the man had previously threatened to post the photos.
The court was told the woman believed it was to blackmail her into removing a protection order.
After discovering the pictures, the woman became very depressed, the court heard.
Judge Colin Doherty said the images were intimate and private but he found that on the evidence the distress caused did not meet the threshold of serious emotional distress.
Netsafe executive director Martin Cocker said the case didn't pass the test.
"The thing with the law is that you have to both prove a breach of the communications principles, and then also prove that it caused serious emotional distress.
"Serious emotional distress is a very high bar, so in this case the judge has said that it didn't pass that second test."
The head of Wellington Sexual Abuse Help Foundation, Conor Twyford, said the judge made a mistake as the woman was clearly distressed.
"We hear that the woman became frustrated, anxious and upset, she didn't recall taking any time off from work but felt unfit for work.
"Those all sound like symptoms of someone who has experienced a level of sexual abuse."
Ms Twyford said the decision would have a lasting impact on the woman. She believed the Act may need to be strengthened.
Women's Refuge chief executive Ang Jury said the ruling was disappointing given there was clear intent to cause harm to the woman.
"Clearly her stoicism and her desire to keep herself together have counted against her. You know, if she'd fallen apart and taken a month of and gone on medication - you know, she was being strong, she was doing everything that she could within the legislation."
Mrs Jury said she was worried about how future cases of a similar nature would be dealt with.
Christchurch lawyer Kathryn Dalziel backed the police decision to appeal the ruling, saying the judge set the threshold too high.
But she said the Harmful Digital Communications Act would work.
"The judge spent some time working through the various elements of the offence, and I think that's useful as we're developing our understanding of it.
"But when it came down to the question of whether or not she'd suffered serious harm, that's where I disagree."
The woman should also complain to the privacy commissioner, she said. Previously, this type of case may have fallen under the definition of domestic affairs and not warrant the intervention of the Privacy Act, but an exception came in last year.
"That says that if personal information [that] is collected, disposed or used, would be highly offensive to an ordinary person, then that was an exception that would allow this material to come into the ambit of the Privacy Act."
Mr Cocker said New Zealand brought in the Harmful Digital Communications Act ahead of most other countries but it would need to be reviewed, including elements like the emotional distress threshold.
"There have been a number of successful prosecutions under the Act. This was an unsuccessful one. When we've had enough cases go through then we can make a decision and say if [the emotional distress threshold] is set at the right level or not."
Mr Cocker said hundreds of people had asked for help since it launched a new hotline late last year.