Louise Dallas Mitchell was convicted of one count of violating the Georgia Controlled Substances Act. She appeals the denial of her motion for new trial. We affirm.
1. Mitchell challenges the sufficiency of the evidence to sustain her conviction. “On appeal the evidence must be viewed in the light most favorable to support the verdict, and appellant no longer enjoys a presumption of innocence; moreover, an appellate court . . . does not weigh the evidence or determine witness credibility.” (Citation and punctuation omitted.) Powell v. State, 218 Ga. App. 556 (462 SE2d 447) (1995). So viewed, the evidence shows that undercover agent Jerald Dalton of the Georgia Bureau of Investigation went to Mitchell’s house, asked Mitchell to sell him some cocaine, and gave Mitchell $200. Mitchell then gave a quantity of crack cocaine to Dalton. After she was arrested and advised of her Miranda rights, Mitchell also signed a confession. This evidence is sufficient. See Jackson v. Virginia, 443 U. S. 307 (99 SC 2781, 61 LE2d 560) (1979); Williams v. State, 218 Ga. App. 571, 572 (1) (462 SE2d 457) (1995).
2. Mitchell alleges that the trial court committed harmful error by allowing lead investigating officer James Perry to “violate the rule of sequestration.” Before testimony began Mitchell’s counsel asked that all witnesses, specifically including Perry, be sequestered, or that Perry be required to testify first if he was not sequestered. It is apparent from the colloquy between the court and defense counsel that Perry, as the lead investigating officer in the case, had remained in the courtroom to assist the prosecuting attorney during Mitchell’s first trial, which had ended in a hung jury. In this first trial, Perry had testified after other State witnesses, and it is apparent that defense counsel and the court expected the prosecution to desire Perry to remain in the courtroom at counsel table to assist the prosecutor during the second trial also. The trial court denied the sequestration request as to Perry on the ground that Perry had already tes*879titled at the first trial and was therefore subject to impeachment if he changed his testimony. Perry was the second witness called by the State, was recalled for further testimony after Agent Dalton testified, and was called a third time after Mitchell testified. Mitchell objected to Perry’s being recalled after Dalton’s testimony, and the trial court overruled the objection.
OCGA § 24-9-61 provides: “[I]n all cases either party shall have the right to have the witnesses of the other party examined out of the hearing of each other. The court shall take proper care to effect this object as far as practicable and convenient, but no mere irregularity shall exclude a witness.” However, “the trial court, in the exercise of its discretion, was authorized to permit the chief investigating officer to remain and assist in the orderly presentation of the State’s case.” Johnson v. State, 198 Ga. App. 316 (4) (401 SE2d 331) (1991). The trial court did not abuse its discretion in allowing the lead investigator to remain in the courtroom.
Mitchell also argues that it was error to allow Perry to be recalled to testify multiple times. Pretermitting the question of whether Mitchell’s enumeration of error was specific enough to raise this issue, the trial court has discretion to allow such repeated testimony by an unsequestered lead investigator. Dunbar v. State, 209 Ga. App. 97 (1) (432 SE2d 829) (1993). We find no abuse of discretion here.
3. Mitchell also alleges error in the court’s overruling of his objection to and motion to strike a comment by Agent Dalton, which Mitchell contends impermissibly expressed Dalton’s opinion that Mitchell was guilty. Dalton testified that he would not overstate his certainty in his eyewitness identification of Mitchell because “[m]y job is not to put innocent people in jail, only the people who commit these acts of crime.”
“Ordinarily, a witness may not express his opinion as to an ultimate fact, because to do so would invade the province of the jury.” Fordham v. State, 254 Ga. 59 (4) (325 SE2d 755) (1985). When a witness states such an impermissible opinion, however, the error may be cured by appropriate remedial action of the trial court. See Grayer v. State, 181 Ga. App. 845, 846 (1) (354 SE2d 191) (1987). Such an error may also be harmless where the evidence against the defendant is overwhelming, and the court instructs the jury that they alone are to decide the case’s outcome. See Nolton v. State, 196 Ga. App. 690, 691-692 (2) (396 SE2d 605) (1990).
In the case before us, any conclusion implied by Agent Dalton’s comment was merely cumulative of the obvious import of his explicit and proper testimony, summarized in Division 1 above. Moreover, the court charged the jury on the presumption of innocence; the State’s burden to prove guilt, including identity, beyond a reasonable *880doubt; the evaluation of identification testimony; the elements of the charged offense; and the jury’s exclusive responsibility to decide guilt or innocence. Any error in overruling this objection was thus harmless because, like the erroneous admission of conclusory testimony in Carroll v. State, 185 Ga. App. 857, 858-859 (1) (366 SE2d 232) (1988), “in the context of the other evidence it is highly probable that the error did not contribute to the judgment.” (Citation and punctuation omitted.) Id. at 858. See generally Palmer v. State, 186 Ga. App. 892, 901 (4) (369 SE2d 38) (1988).
Judgment affirmed.
McMurray, P. J., Birdsong, P. J, Pope, P. J., Andrews and Smith, JJ., concur. Beasley, C. J., concurs specially. Blackburn and Ruffin, JJ., concur in part and dissent in part.