Guernsey Police have been issued a reprimand for breaching Data Protection Law.
The Data Protection Authority has found it contravened section 6(2)(a) of the law by not processing special category personal data 'in a lawful, fair and transparent manner'.
It says a person's personal information was processed without the necessary consent.
A complaint was made to the ODPA, which found the Police were 'unclear' on compliance around the sharing of data.
However, the Authority says there are mitigating factors in that it was single case; no other complaints have been made about Guernsey Police in relation to such processing; the force destroyed the shared information and the parties who had received it confirmed its destruction.
Guernsey Police is reviewing its procedures and cooperated with the Authority.
"Considering the above factors, the Authority has, by written notice to Guernsey Police imposed a formal enforcement order to bring specified processing operations into compliance and a reprimand for the lack of compliance." - ODPA
Head of Law Enforcement Ruari Hardy says Guernsey Police takes the protection of personal data very seriously.
"We are here to serve the community so when members of the public come forward to seek our help, we hold ourselves to the highest standards to ensure they receive the support they need.
"In essence that is what led to the data protection breach the Office of the Data Protection Authority has confirmed today. Officers believed an individual needed help, acted in good faith and did what they considered to be in the best interests of the person by sharing their personal data with two professional health teams.
"Nevertheless, despite those best of intentions we accept the ruling of the ODPA and have sought to learn from it."

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