Say what? It’s not a federal crime to make a false report to the Chicago police. That’s a local LE matter.
Federal jurisdiction can be bootstrapped if Smollet used any wire service to advance his fraud, including the Intarweb.
But it is a Federal Crime when someone sends a (HOAX) Hate Letter full of White Powder through the U.S. Post Office.
The FBI was called in due to federal hate crime laws. And I'm sure sure federal postal investigators were called in because the mail was used to deliver that letter a week earlier. Plenty of of reasons for the feds to be involved because this was much more than just filing a false police report. That's just one of the numerous charges.