On March 8th, the Ontario Superior Court of Justice issued an endorsement that outlined the rule on when relevant information may be redacted from producible records. It said, “The whole of a relevant document must be produced except to the extent it contains information that would cause significant harm to the producing party or would infringe public interests deserving of protection.” And also, “Irrelevance alone is not a sufficient ground on which to redact portions of a document. The party seeking to do so bears the onus of establishing that redaction is necessary to protect an important interest.”
McGee v. London Life Insurance Company Limited, 2010 ONSC 1408 (CanLII).