
461 S.E.2d 533 (1995)
265 Ga. 688
FLOWERS
v.
The STATE.
No. S95A1329.
Supreme Court of Georgia.
September 25, 1995.
*534 Elliott A. Shoenthal, Decatur, for Torrey Flowers.
J. Tom Morgan, Dist. Atty., Barbara B. Conroy, Sp. Asst. Dist. Atty., Decatur, Michael J. Bowers, Atty. Gen., Department of Law, Susan V. Boleyn, Senior Asst. Atty. Gen., Richard J. Warren, Asst. Atty. Gen., Atlanta, Michael McDaniel, Asst. Dist. Atty., Decatur, for the State.
CARLEY, Justice.
After a jury trial, appellant was found guilty of two offenses: felony murder while in the commission of a kidnapping with bodily injury; and, armed robbery. He appeals from the judgments of conviction and the consecutive sentences of life imprisonment that were entered on the jury's guilty verdicts.[1]
1. The State produced evidence showing that appellant and several others used guns to force the victim from a phone booth into his car. They then drove the victim to another location, shot him, took his ring and car, and sold his car for $500 and cocaine. Moreover, appellant admitted some involvement in the crimes. The victim died two days after the shooting. Based upon this evidence, the jury was authorized to find appellant guilty of felony murder and armed robbery beyond a reasonable doubt. Jackson v. Virginia, 443 U.S. 307, 99 S.Ct. 2781, 61 L.Ed.2d 560 (1979); Arline v. State, 264 Ga. 843(1), 452 S.E.2d 115 (1995); Bedford v. State, 263 Ga. 121, 122(3), 429 S.E.2d 87 (1993).
2. Appellant unsuccessfully sought to exclude his statements from evidence on the ground that they were not made voluntarily. Although appellant did offer expert testimony that his mental age was eight years, a "mere showing that one who confessed to a crime may have suffered from some mental disability is not a sufficient basis upon which to exclude the statement. [Cits.]" Corn v. State, 240 Ga. 130, 136(3), 240 S.E.2d 694 (1977). See also Willis v. State, 263 Ga. 597, 599(2), 436 S.E.2d 204 (1993); Marshall v. State, 248 Ga. 227, 229, 282 S.E.2d 301 (1981); Goodwin v. State, 236 Ga. 339, 342(1), 223 S.E.2d 703 (1976) (mental age of nine years); Farley v. State, 145 Ga.App. 98, 99(1), 243 S.E.2d 322 (1978) (mental age of less than five years). When all of the evidence regarding the voluntariness of appellant's statements is considered, the trial court's finding that those statements were admissible is not clearly erroneous. See generally Marshall v. State, supra, 248 Ga. at 228(3), 282 S.E.2d 301.
3. Because appellant was originally detained as a juvenile, he urges that it was error to indict and try him as an adult without first conducting a transfer hearing. Appellant's reliance upon In the Interest of C.R., 263 Ga. 155, 430 S.E.2d 3 (1993) as authority for this contention is misplaced. In the Interest of C.R. held only that jurisdiction vests in the juvenile court upon receipt of a juvenile complaint form. Here, no juvenile complaint form was filed prior to appellant's indictment and In the Interest of C.R. is, therefore, inapplicable. Moreover, we no longer follow In the Interest of C.R. "as to the jurisdictional effect of a written juvenile complaint form." State v. Whetstone, 264 Ga. 135, 136, 441 S.E.2d 842 (1994). As was recognized by Whetstone, supra at 136, 441 S.E.2d 842, "the filing of a juvenile complaint form alone may commence informal proceedings...." See In the Interest of B.W.S., 265 Ga. 567(1), 458 S.E.2d 847 (1995). However, exclusive jurisdiction vests in the juvenile court only when a petition of delinquency is filed. State v. Whetstone, supra. Here, no petition of delinquency was filed prior to appellant's indictment. It was, therefore, not *535 error to indict and try appellant as an adult without first conducting a transfer hearing.
4. Because one of the participants in the crimes was afforded treatment as a juvenile, it is urged that appellant's treatment as an adult constitutes unconstitutional selective prosecution. However, the one participant who was treated as a juvenile was shown to be the least culpable. Accordingly, the trial court did not err in denying appellant's motion to dismiss on the ground of selective prosecution. See Sabel v. State, 250 Ga. 640, 643(4), 300 S.E.2d 663 (1983); Gayton v. State, 184 Ga.App. 387, 388, 361 S.E.2d 691 (1987); George v. State, 175 Ga.App. 229, 230(2), 333 S.E.2d 141 (1985).
5. Over appellant's objection, the trial court admitted evidence that two other participants in the crimes were in possession of cocaine at the time of their arrests. This evidence was admissible to corroborate appellant's statement that the victim's automobile had been sold for $500 and cocaine and to show the motive for the crimes. See James v. State, 223 Ga. 677, 685(7), 157 S.E.2d 471 (1967); Sabree v. State, 195 Ga. App. 135, 137(2), 392 S.E.2d 886 (1990); Carruth v. State, 182 Ga.App. 786, 787(2), 357 S.E.2d 122 (1987).
Judgments affirmed.
All the Justices concur.
NOTES
[1]  The crimes occurred on September 9, 1993. Appellant was indicted on September 13, 1993. The verdicts were returned on November 17, 1994 and the sentences were imposed on December 9, 1994. Appellant's motion for new trial was filed on January 6, 1995, amended on March 29, 1995 and denied on March 30, 1995. His notice of appeal was filed on April 19, 1995. The case was docketed in this court on May 15, 1995 and was submitted for decision on July 10, 1995.
