What rights do a prisoner have in the context of freedom of speech?

Incarcerated persons do not enjoy the full panoply of constitutional rights that non-incarcerated individuals do. See Pell v. Procunier , 417 U.S. 817, 822, 94 S.Ct. 2800, 41 L.Ed.2d 495 (1974) ("[L]awful incarceration brings about the necessary withdrawal or limitation of many privileges and rights, a retraction justified by the considerations underlying our penal system." (internal quotation marks omitted)). A prisoner retains only "those First Amendment rights that are not inconsistent with his status as a prisoner or with the legitimate penological objectives of the corrections system," such as the goal of maintaining institutional safety and security. Id.