Trista Oettle wanted to take a “ballot selfie” when she voted in Clinton County, 37 miles east of St. Louis, on Nov. 6, 2018. But she backed off after an election judge told her she “would go to prison” if she did. This warning was based on Section 29-9 of the Illinois Election Code. Under Section 29–9 (“Unlawful observation of voting,”) “any person who knowingly marks his ballot or casts his vote on a voting machine or voting device so that it can be observed by another person” is guilty of a Class 4 felony. In a state …