“Where a party inadvertently allows a privileged document to be inspected, the party who has inspected the document may use it or its contents only with the permission of the court.”
“Those principles seem to us also to apply to cases where the documents were not initially the subject of LPP privilege but in respect of which the disclosing party was entitled to claim PII. Once it is accepted that the party concerned is not bound to refuse to permit inspection of a relevant document we can see no reason why (in the absence of particular circumstances in a particular case) different principles should apply to the two situations.”