There are several Midwest states that require permits or have other restrictions, including Indiana, Minnesota, Kentucky and Michigan.
Illinois has no such restrictions thanks to the efforts of CARMA and SABRE members who lobbied legistators in Springfield and Chicago to beat back proposed IL state laws and a Chicago city ordinance that would have prohibited or restricted scanner use. As a result the Chicago City Council passed a reasonable ordinace that prohibits the use of a scanner in the commission of a crime.