Penal institution means any institution used to house or detain a person who is convicted of a crime; or who is in direct or indirect custody after a lawful arrest. It is an institution where persons are confined for punishment. Penal institution can be a prison, jail, correction facilities, or any other detention centers.
The following is an example of state law (Texas) defining the term:
According to Tex. Code Crim. Proc. art. 24.29, "Penal institution" means a jail, prison, penitentiary, house of correction, or other place of penal detention.