7th circuit court of appeals decision
Prison Mail – Access to Courts
As a matter of the due process right to a fair hearing in a civil matter, which includes the right to aid of counsel, a prison inmate is entitled to receive confidential communications from his lawyer. However, the prison is entitled, as a matter of security, to assure itself that such purported communications are indeed from a lawyer authorized to practice in the relevant jurisdiction. These competing considerations are accommodated by permitting prison staff to open putative legal mail for verification purposes but only in the inmate’s presence.
Protection of the privacy of attorney mail in this fashion is imperfect; the prison employee who opens the letter will have to glance at the content to verify its bona fides. But the imperfection is necessary to protect the prison’s interest in security—and is lessened by allowing prisoners to engage in unmonitored phone conversations with their lawyers. Wisconsin allows this, Wis. Admin. Code § DOC 309.39(6)(a), as do federal regulations in the case of federal prisoners. See 28 C.F.R. § 540.102; see also United States v. Novak, supra, 531 F.3d at 100-04.
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… We think there must likewise by a showing of hindrance in a claim of interference with a prisoner’s communications with his lawyer.
But proof of a practice of reading a prisoner’s correspondence with his lawyer should ordinarily be sufficient to demonstrate hindrance. …
An isolated interference with the confidentiality of such communications is different; its effect on prisoners’ access to justice is likely to be nil. …
