In her judgement, Judge Doogue said the deputy chief executive's refusal to grant an interview request was a disproportionate limitation on Smith's right to freedom of expression.
She said the two primary reasons given to decline the interview request, in the interests of Smith's victims and the risk to his personal safety, were not rationally connected to the evidence and the decision "was unreasonable in administrative law terms".
Smith appeared by audiovisual link in the High Court at Wellington earlier this month, where, self-represented, he argued he should be allowed to have an in-person interview with a journalist.
He said the decision by the Corrections deputy chief executive to decline the face-to-face meeting was "unreasonable" and did nothing to address the victims' interests, given Corrections had agreed to allow him to be interviewed via written correspondence instead.
"In broad terms, if the interview was allowed to proceed by correspondence then the victim interests could not be protected in the way he intended," he said.
Smith also said too much weight was given to the victims' views on the matter, and that the fact they had done media interviews of their own volition over the past 23 years showed they were able to "absorb" negative effects from that publicity.
If he was to be interviewed, it would not cause any greater negative effects for the victims than what they had already experienced through prior media coverage they had agreed to, he said.
"If they chose not to view the content, then there can be no harm."
Smith spoke of his "treatment" by Corrections since his return from South America, saying the courts had repeatedly found his human rights were not respected.
He pointed to being unlawfully kept in prolonged solitary confinement as one example.
"The court has acknowledged in numerous judgments that it appeared that the motivation for the respondent's decision making was punitive."
Lawyer for Corrections Genevieve Taylor said the reason a written interview was permitted but not a face-to-face one was that such an interview would hold "greater immediacy and detail" as an "exclusive interview with Mr Smith in Rimutaka Prison".
More publicity would be given to it and would provide more opportunity to cause harm to the victims through "continued exposure to Mr Smith in the media".
She said the proposed interview topics focused on Smith, his history, and his plans for the future, and that this was not of enough public interest to grant the interview.
The respondent gave appropriate consideration to the balance between protecting the victims and allowing Smith freedom of expression, she said.
Corrections has been directed to reconsider the decision in light of the High Court judgement.