If you're interested in listening to Chicago mayhem, invest in a quality police & fire scanner, such as:

• NEW! Uniden BCD996P2
• NEW! Uniden BCD325P2
• Uniden BCD396XT
• Uniden BC75XLT
• Uniden BCD996XT

or a cheaper two-way radio, like the:

• Baofeng UV5RA
• Baofeng UV-5R V2+
• BaoFeng BF-F8+

If you're not local, head over to either the Apple or Google app store and download a scanner app or check out Broadcastify's Live Audio Feeds.