And legal experts say he's completely within his rights.

As a prosecutor, Dozier has the power to decide which cases he will and won't pursue, though it is unusual to publicly announce that a whole class of offenses is off the table, American University law professor Angela Davis said.

Also rare is basing that decision on the prosecutor's own opinion that a law is invalid, she said.

"I'm not saying it's never been done, but it's certainly not common," said Davis, author of "Arbitrary Justice: The Power of the American Prosecutor."

Dozier believes many state's attorneys have privately decided not to pursue charges against people who violate some of Illinois' gun laws, such as failing to properly store a gun or allowing their state-issued Firearm Owners Identification Card to expire.