www.bbc.co.uk/news/uk-scotland-52896427I
Mark Sutherland has appealed his conviction for paedophile offences on grounds of invasion of privacy, because he was caught by a vigilante group.
In another case
"lawyers said the vigilantes' activities interfered with his rights under ECHR Article 8 and using their evidence in any trial would mean the court was acting "incompatibly" with those rights.
They also argued the use of information gathered covertly was unlawful under legislation designed to to ensure the surveillance of a person was properly regulated.
Those arguments were rejected by the sheriff, but he said by pretending falsely to be young children, the vigilantes had acted unlawfully.
The judgement, which will be issued later, will provide a definitive answer to the question of whether undercover vigilante activity is legal, and compatible with human rights, even of those who seek to abuse children."