28 CFR § 527.30
Purpose and scope
July 24, 2020
The Bureau of Prisons will consider a request made on behalf of a state or local court that an inmate be transferred to the physical custody of state or local agents pursuant to state writ of habeas corpus ad prosequendum or ad testificandum. The Warden at the institution in which the inmate is confined is authorized to approve this transfer in accordance with the provisions of this rule.