In Guyer v. Beard, 907 F.2d 1424 (3d cir. 1990), a prisoner refused to sign a power of attorney form, and, as a result, the warden would not deliver his mail. Guyer sought an order compelling the prison officials to deliver his mail to him. However, the warden explained that a United States Postal Service (USPS) regulation requires that inmates sign a power of attorney in order to authorize the prison to receive an inmate's mail. The regulation allows prisons to open, examine and censor the mail addressed to an inmate "if the inmate-addressee consents to receive his mail at the institution through the institutional authorities." Guyer, 907 F.2d at 1428 n.9. Pennsylvania regulations require that prison officials open and examine incoming mail. Thus, because Guyer refused to sign a power of attorney form, the warden returned his incoming mail to the post office. The court denied the request to compel the delivery of Guyer's mail. Guyer.