Reversing the court of appeals, the court held the evidence necessary to prove a defendant guilty under the theory of acting in concert is not the same as that necessary to establish the aggravating factor that the defendant joined with more than one other person in committing the offense and was not charged with committing a conspiracy. Because the aggravating factor requires additional evidence beyond that necessary to prove acting in concert, the trial court properly submitted the aggravating factor to the jury. Specifically, the aggravating factor requires evidence that the defendant joined with at least two other individuals to commit the offense while acting in concert only requires proof that the defendant joined with at least one other person. Additionally, the aggravating factor requires proof that the defendant was not charged with committing a conspiracy, which need not be proved for acting in concert.