Police investigating a murder in north Belfast had legal power to video record a child at her home, the Court of Appeal ruled on Tuesday.
enior judges rejected claims that footage of the nine-year-old girl was unlawfully taken during searches linked to the killing of taxi driver Michael McGibbon.
Lord Justice McCloskey held that the images were captured "fleetingly" amid a carefully planned operation.
He said: "The conduct of the police officer concerned was the very antithesis of the arbitrary or unconstrained."
Mr McGibbon, 33, died after being shot three times in the legs in the Ardoyne area back in April 2016.
Police hunting for the suspected dissident republican murderers carried out a search at the girl's home four months later.
The child's mother and her partner were arrested but later released unconditionally.
During the operation an evidence gathering team video-taped members of the family, including incidental footage of the girl.
Her mother issued proceedings against the PSNI, claiming the policy or practice of using the recording methods and retaining film obtained from searches of a home breached privacy rights.
She stated her children had suffered distress by strangers entering their house in the morning and video-taping them as they got out of bed.
Some of the footage depicted the girl in her mother's arms, clinging to her neck.
A police search advisor provided evidence that the background to the search was a fatal gun attack involving a claim of responsibility by the 'New IRA'.
Mr McGibbon had been threatened at his home by unidentified men claiming to be the IRA, it was previously disclosed.
Police argued that the search was authorised by a detective inspector, with the evidence gathering team's intention to provide impartial, non-edited evidence and avoid any malicious complaints.
The operation was staged at a reasonable time and without rapid entry, according to the PSNI.
In May 2018 the High Court held that images of the child were incidentally captured during a lawful search for any weapons and recording equipment during a murder investigation.
A separate challenge to retention of the footage was subsequently also dismissed.
Ruling on the appeal against those findings, Lord Justice McCloskey evaluated PSNI policy against Article 8 of the European Court of Human Rights.
He stressed that police activity throughout the search operation was not under scrutiny.
"It is confined to the incidental, peripheral and, realistically, unavoidable capturing of fleeting images of the appellant during a matter of minutes," he said.
"Furthermore, this was no covert act. Rather, it was overt in its entirety, involving the use of a device which would have been familiar, and was visible to, all present."
Dismissing the appeal, the judge added: "The planning of this search operation was meticulous, the operational decision at the planning stage to make the offending recording was the product of careful consideration, weighing a range of material factors and the execution of this discrete decision involved no arbitrary or abusive conduct."