¶1concurring specially.
¶2I concur fully in Divisions 1, 3 and 4 of the majority opinion, as well as in the affirmance of Ms. Davis’ conviction and sentence. In Division 2, however, the majority concludes that the admission of Ms. Davis’ 1991 guilty plea to a charge of aggravated assault with a knife, for which she received first offender treatment, was harmless error. In my opinion, the admission of the guilty plea was not error. Therefore, I concur specially.
¶3Clearly, the guilty plea could not be used in connection with any issue requiring proof of Ms. Davis’ conviction of the prior aggravated assault. OCGA § 42-8-62; Matthews v. State, 268 Ga. 798 (493 SE2d 136) (1997) (impeachment on general credibility grounds). Compare Hightower v. General Motors Corp., 255 Ga. 349 (338 SE2d 426) (1986) (impeachment by disproving and contradicting first offender’s testimony). However, a defendant’s commission of a prior offense need not have resulted in a conviction to be admissible as “other crimes” evidence in a subsequent criminal trial. Tilley v. State, 197 Ga. App. 97, 98 (2) (397 SE2d 506) (1990). The admissibility of “prior act” evidence is dependent only upon its similarity to the criminal charge for which the defendant is being tried and its relevance to proving the defendant’s commission of that charge. Williams v. State, 251 Ga. 749, 755 (4) (312 SE2d 40) (1983).
¶4Here, there was testimony concerning the prior aggravated assault, as well as the evidence of Ms. Davis’ guilty plea. This testimony was certainly admissible to show the similarity of the prior aggravated assault to that for which Ms. Davis was being tried. Haywood v. State, 220 Ga. App. 182 (1) (469 SE2d 206) (1996); Tilley v. State, supra at 98 (2). In Stephens v. State, 261 Ga. 467, 468 (6) (405 SE2d 483) (1991), we held that it was error to admit a certified copy *282of a prior conviction without additional evidence of similarity. Until today, we have never held that it is error to admit a defendant’s guilty plea simply because there is additional evidence of similarity. Evidence of prior similar crimes is not limited to convictions, and such evidence can be admitted if illustrative of relevant issues in a subsequent criminal trial.
¶5The underlying humanitarian purpose of the First Offender Act is completely served by prohibiting the State’s use of a guilty plea in connection with any issue requiring proof of the defendant’s prior conviction. Although Ms. Davis has no prior convictions, it does not follow that she did not commit a prior criminal offense. The First Offender Act was never intended to insulate the defendant from all of the consequences of violating the criminal laws of Georgia and to prohibit the State from using a first offender guilty plea, as distinguished from the first offender record, for a relevant evidentiary purpose should the defendant allegedly commit a subsequent similar offense. Here, the guilty plea was not offered to show Ms. Davis’ prior conviction for any offense, but to show that she admitted commission of a previous aggravated assault with a knife. Unlike the majority, I believe that this evidence was admissible as part of the State’s proof of Ms. Davis’ commission of a prior aggravated assault which was similar to that for which she was now being tried. Since the trial court properly admitted the evidence, the question of harmless error never arises.
¶6I am authorized to state that Justice Hunstein and Justice Hines join in this special concurrence.