28 CFR § 511.17
When a non-inmate will be denied entry to or required to leave a Bureau facility or Bureau grounds
July 24, 2020
At the Warden's, or his/her designee's, discretion, and based on this subpart, you may be denied entry to, or required to leave, a Bureau facility or Bureau grounds if:
(a) You refuse to be searched under this subpart; or
(b) There is reasonable suspicion that you may be engaged in, attempting, or about to engage in, prohibited activity that jeopardizes the Bureau's ability to ensure the safety, security, and orderly operation of its facilities, or protect the public. “Reasonable suspicion,” for this purpose, may be based on the results of a search conducted under this subpart, or any other reliable information.