(720 ILCS 5/3-4) (from Ch. 38, par. 3-4)

Sec. 3-4. Effect of former prosecution.

(a) A prosecution is barred if the defendant was formerly prosecuted for the same offense, based upon the same facts, if that former prosecution:

(1) resulted in either a conviction or an acquittal or in a determination that the evidence was insufficient to warrant a conviction;

(2) was terminated by a final order or judgment, even if entered before trial, that required a determination inconsistent with any fact or legal proposition necessary to a conviction in the subsequent prosecution; or

(3) was terminated improperly after the jury was impaneled and sworn or, in a trial before a court without a jury, after the first witness was sworn but before findings were rendered by the trier of facts, or after a plea of guilty was accepted by the court.

A conviction of an included offense, other than through a plea of guilty, is an acquittal of the offense charged.

(b) A prosecution is barred if the defendant was formerly prosecuted for a different offense, or for the same offense based upon different facts, if that former prosecution:

(1) resulted in either a conviction or an acquittal, and the subsequent prosecution is for an offense of which the defendant could have been convicted on the former prosecution; or was for an offense with which the defendant should have been charged on the former prosecution, as provided in Section 3-3 of this Code (unless the court ordered a separate trial of that charge); or was for an offense that involves the same conduct, unless each prosecution requires proof of a fact not required on the other prosecution, or the offense was not consummated when the former trial began;

(2) was terminated by a final order or judgment, even if entered before trial, that required a determination inconsistent with any fact necessary to a conviction in the subsequent prosecution; or

(3) was terminated improperly under the circumstances stated in subsection (a), and the subsequent prosecution is for an offense of which the defendant could have been convicted if the former prosecution had not been terminated improperly.

(c) A prosecution is barred if the defendant was formerly prosecuted in a District Court of the United States or in a sister state for an offense that is within the concurrent jurisdiction of this State, if that former prosecution:

(1) resulted in either a conviction or an acquittal, and the subsequent prosecution is for the same conduct, unless each prosecution requires proof of a fact not required in the other prosecution, or the offense was not consummated when the former trial began; or

(2) was terminated by a final order or judgment, even if entered before trial, that required a determination inconsistent with any fact necessary to a conviction in the prosecution in this State.

(d) A prosecution is not barred within the meaning of this Section 3-4, however, if the former prosecution:

(1) was before a court that lacked jurisdiction over the defendant or the offense; or

(2) was procured by the defendant without the knowledge of the proper prosecuting officer, and with the purpose of avoiding the sentence that otherwise might be imposed; or if subsequent proceedings resulted in the invalidation, setting aside, reversal, or vacating of the conviction, unless the defendant was thereby adjudged not guilty.

(Source: P.A. 96-710, eff. 1-1-10.)