As the election approaches people have been asking whether they can legally take a selfie of their ballot when casting their vote in Illinois. The short answer is that you cannot do so legally. If you are caught taking a selfie of your ballot you could be charged with a class 4 felony offense. The text and citation of the statute is:
(10 ILCS 5/29-9) (from Ch. 46, par. 29-9)
Sec. 29-9. Unlawful observation of voting. Except as permitted by this Code, 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, and any person who knowingly observes another person lawfully marking a ballot or lawfully casting his vote on a voting machine or voting device, shall be guilty of a Class 4 felony.
(Source: P.A. 78-887.)
Illinois law conflicts with other states and is consistent with other states. There is no uniformity to the law throughout the nation. The purpose of the criminal penalty is to avoid interfering with other voters' who are attempting to cast their vote in adjacent booths. The popularity of selfies cannot be denied. Presumably voters will unintentionally violate the above-cited portion of the elction code on November 8th when taking selfies of themselves in the voting booth. I doubt these persons would be prosecuted unless it was a repeat offender who continues this action after previously being advised not to do so.
Hopefully voters do not run afoul of the law through ignorance of this Illinois law.