730 ILCS 5/3-10-12
The Director of the Department of Juvenile Justice may authorize the use of any institution or facility of the Department of Juvenile Justice as a Juvenile Detention Facility for the confinement of minors under 16 years of age in the custody or detained by the Sheriff of any County or the police department of any city when said juvenile is being held for appearance before a Juvenile Court or by Order of Court or for other legal reason, when there is no Juvenile Detention facility available or there are no other arrangements suitable for the confinement of juveniles. The Director of Juvenile Justice may certify that suitable facilities and personnel are available at the appropriate institution or facility for the confinement of such minors and this certification shall be filed with the Clerk of the Circuit Court of the County. The Director of Juvenile Justice may withdraw or withhold certification at any time. Upon the filing of the certificate in a county the authorities of the county may then use those facilities and set forth in the certificate under the terms and conditions therein for the above purpose. Juveniles confined, by the Department of Juvenile Justice , under this Section, must be kept separate from adjudicated delinquents.
730 ILCS 5/3-10-12