Robert McIntyre was tried before a jury and found guilty of murder. He appeals from the judgment of conviction and life sentence entered by the trial court on the jury’s guilty verdict. 1
1. When the evidence is construed most strongly in favor of the State and against McIntyre, the jury was authorized to find the following: McIntyre became a member of a Satanic group of which Terry Chapman was the leader. Malisa Earnest and the victim were runaways who were given shelter by Chapman. The victim rejected McIntyre’s sexual advances. Subsequently, McIntyre, Chapman and Ear*8nest discussed killing the victim and agreed to strangle her with the lace from a boot. Earnest put the lace around the victim’s neck and, when she began to struggle, Chapman took the lace and tightened it. McIntyre then took the lace and, placing his knee to the victim’s back, tightened it around her neck. McIntyre and Chapman tied a double knot in the lace and sat on either side of the victim’s body. Holding hands, they recited a satanic chant. After wrapping the body in a blanket, they buried it in the nearby woods. The next day, McIntyre took his mother’s van and he, along with Chapman and Earnest, fled the state. McIntyre’s parents reported that he and the van were missing. An officer in Louisiana stopped the van after determining that it was reported as stolen and the occupants were reported as missing juveniles. The Georgia authorities were contacted and they requested that McIntyre and Chapman be detained as runaways in possession of a stolen vehicle. After receiving Miranda warnings, McIntyre and Chapman were placed in a cell. Although Earnest was not detained, she was, at her request, allowed to stay in a cell near that which housed McIntyre and Chapman. During the night, Earnest volunteered to her cellmate that she and McIntyre and Chapman had committed a murder. In the hearing of Earnest’s cellmate, the three then openly discussed the murder and the burial of the victim’s body. The next morning, Earnest left for Georgia by bus and McIntyre and Chapman were taken before the juvenile court where they gave their consent to be returned to Georgia. Meanwhile, Earnest’s cellmate reported to the Louisiana authorities the admissions which she heard regarding the murder. The Georgia authorities were contacted and the victim’s body was discovered. When McIntyre and Chapman arrived in Georgia, they were taken into custody. McIntyre was advised of the murder charge and given his Miranda warnings. He made no statement to the officers but, when his mother arrived, he made a statement to her in the presence of the sheriff. In this statement, McIntyre admitted to his mother that he “tied the knot off.” Chapman and Earnest were tried and convicted. Chapman v. State, 259 Ga. 592 (385 SE2d 661) (1989); Earnest v. State, 262 Ga. 494 (422 SE2d 188) (1992). Chapman testified for the State and his testimony was corroborated in several material respects. McIntyre presented no evidence in his defense.
This evidence was sufficient to authorize a rational trier of fact to find proof of McIntyre’s guilt of murder beyond a reasonable doubt. Jackson v. Virginia, 443 U. S. 307 (99 SC 2781, 61 LE2d 560) (1979).
2. During the trial, Judge Robert Noland initially presided, but had to leave during the State’s presentation of evidence in order to attend the funeral of his infant grandson. Judge Robert James replaced Judge Noland over McIntyre’s objection. McIntyre contends that the substitution of judges constituted a violation of his Sixth and *9Fourteenth Amendment rights. We assume, for purposes of this appeal only, that these rights are implicated by a midtrial substitution of judges. But see People v. Espinoza, 12 Cal. Rptr. 2d 682, 695 (1992).
It is the general rule that any error in the substitution of judges is subject to harmless error analysis. Jimenez v. State, 838 SW2d 661, 666 (Tex. App. 1992); United States v. Boswell, 565 F2d 1338, 1342 (5th Cir. 1978); Annot., 73 ALR Fed. 833, 839, § 4; 75 AmJur2d 444, Trial, § 222. The dissent has cited no authority for the proposition that certain substitutions of judges are “structural defects” which require automatic reversal. Indeed, many of the cases cited by the dissent have expressly recognized the possibility of harmless error. One of those cases was decided since Arizona v. Fulminante, 499 U. S. 279 (111 SC 1246, 113 LE2d 302) (1991) and dealt with a midtrial substitution of judges. Hood v. State, 637 A2d 1208, 1213, 1214 (Md. 1994). Although Hood held that the State must rebut a presumption of prejudice or demonstrate beyond a reasonable doubt that the error was harmless, it also recognized “that a number of courts have held to the contrary, and have required that a defendant demonstrate actual prejudice in order to obtain a new trial. . . .” Hood v. State, supra at 1213.
Similarly, in Georgia, the temporary absence of a trial judge without suspension of the trial is not a basis for reversal unless the complaining party shows prejudice resulting from the absence. Koza v. State, 158 Ga. App. 709, 710 (4) (282 SE2d 131) (1981). McIntyre has not shown that he was harmed by the substitution, and therefore, under the circumstances of this case, the procedure followed in the trial court does not require reversal of the judgment of conviction. Jimenez v. State, supra at 666.
3. McIntyre urges that the statement that he made to his mother should have been suppressed as the product of an illegal arrest and impermissible interrogation. However, once the officer in Louisiana determined that the van was reported as stolen and its occupants reported as runaways, he had probable cause to stop the van and arrest its occupants. After his lawful arrest in Louisiana, McIntyre gave valid consent to his return to Georgia in accordance with Article VI of OCGA § 39-3-2. By the time that McIntyre had returned to Georgia, the authorities had discovered the body of the victim and had probable cause to arrest him for murder. After being given his Miranda warnings, McIntyre made no incriminating statement to the sheriff. He did, however, make a spontaneous incriminating statement to his mother in the sheriff’s presence. Arizona v. Mauro, 481 U. S. 520 (107 SC 1931, 95 LE2d 458) (1987). Under these circumstances, McIntyre’s spontaneous statement to his mother was correctly admitted into evidence.
*104. McIntyre requested a charge on impeachment “[b]y proof that the witness has been convicted of a crime of moral turpitude.” However, the trial court refused to give this requested charge, on the ground that no certified copy of the conviction of any of the State’s witnesses had been introduced by McIntyre.
The requirement that a prior conviction be proved by a certified copy is an application of the “best evidence” rule and an objection to proof of a prior conviction by secondary evidence may be waived. Moret v. State, 246 Ga. 5, 6 (3) (268 SE2d 635) (1980). See also O’Toole v. State, 258 Ga. 614, 616 (4), fn. 2 (373 SE2d 12) (1988); Williams v. State, 251 Ga. 749, 799 (12) (312 SE2d 40) (1983). Thus, in the absence of a “best evidence” objection, “a witness’ answer to the effect that he or she has been convicted of a crime is admissible to prove the crime, [cit.].” Williams, supra at 799 (12).
On direct examination, Chapman admitted his conviction for the murder and there was no objection raised by McIntyre. On cross-examination, Chapman again admitted his conviction for the murder and there was no objection raised by the State. Murder is a crime of moral turpitude. It follows that the “best evidence” objection was waived and that Chapman’s prior conviction of a crime of moral turpitude was proved by secondary evidence. Compare O’Toole, supra (no secondary evidence admitted without objection); Mincey v. State, 257 Ga. 500, 501 (1) (360 SE2d 578) (1987) (no secondary evidence admitted without objection); Kimbrough v. State, 254 Ga. 504, 505 (2) (330 SE2d 875) (1985) (no secondary evidence admitted without objection); Williams, supra (objection to secondary evidence raised); Ledesma v. State, 251 Ga. 885, 888 (4) (311 SE2d 427) (1984) (objection to secondary evidence erroneously overruled); Timberlake v. State, 246 Ga. 488, 499 (6) (271 SE2d 792) (1980) (objection to secondary evidence raised). Since Chapman’s prior conviction of a crime of moral turpitude was proved by secondary evidence admitted without objection, it was error to refuse to give McIntyre’s requested charge on impeachment.
However, harm as well as error must be shown for reversal. Wood v. State, 243 Ga. 273, 274 (5) (253 SE2d 751) (1979). The failure to give a requested charge which is authorized by the evidence can be harmless error. Duvall v. State, 259 Ga. 801, 802 (4) (387 SE2d 880) (1990). Even discounting Chapman’s testimony, there was overwhelming evidence of McIntyre’s guilt. Burnette v. State, 165 Ga. App. 768 (1) (302 SE2d 621) (1983). That evidence consists of the admissions of McIntyre, Chapman and Earnest which were heard by Earnest’s cellmate, and McIntyre’s admission to his mother. See Meeker v. State, 249 Ga. 780, 782 (5) (294 SE2d 479) (1982). This evidence was “unrefuted by any other evidence to the contrary.” White v. State, 163 Ga. App. 179, 182 (3) (292 SE2d 875) (1982). Since the evidence *11of McIntyre’s guilt is overwhelming even when Chapman’s testimony is discounted, it is highly probable that the erroneous failure to charge on impeachment by proof of a prior conviction for a crime of moral turpitude did not contribute to the jury verdict. “It was harmless and will not require a new trial. [Cit.]” Duvall v. State, supra at 803 (4). See also Shaaghir v. State, 264 Ga. 492, 493 (3) (448 SE2d 196) (1994).
5. Over McIntyre’s relevancy objection, the trial court allowed the sheriff to testify that, when he attempted to question other purported members of the Satanic group, they “took their rights” and refused to answer his questions.
However, McIntyre has failed to show any prejudice resulting from this passing reference to non-witnesses’ out-of-court invocation of their “rights.” Compare Lingerfelt v. State, 235 Ga. 139 (218 SE2d 752) (1975). Indeed, a witness’ in-court invocation of his Fifth Amendment rights is not necessarily harmful. Parrott v. State, 206 Ga. App. 829, 832 (2) (427 SE2d 276) (1992). See Lawrence v. State, 257 Ga. 423, 425 (3), fn. 3 (360 SE2d 716) (1987). What is harmful is for the trial court to allow the State, once a witness has invoked his Fifth Amendment rights, “in effect, to testify for the witness and circumvent meaningful cross-examination as to obvious inferences. . . .” Lawrence v. State, supra at 425 (3), fn. 3. If a witness’ mere in-court assertion of his Fifth Amendment rights is not necessarily harmful, then a passing reference to non-witnesses’ mere out-of-court assertion of their rights, although irrelevant, is not prejudicial. Accordingly, the trial court erred in failing to sustain McIntyre’s relevancy objection to the sheriff’s testimony, but that error does not require reversal.
6. Evidence regarding satanism was properly admitted as relevant to the motive for the murder. Whitener v. State, 261 Ga. 567 (2) (407 SE2d 735) (1991).
7. The attack which McIntyre makes on the constitutionality of former OCGA § 15-11-5 (b) was rejected in the appeal of Chapman. Chapman, supra.
8. It was not error to fail to give McIntyre’s written request to charge on voluntary manslaughter as a lesser included offense, since there was no evidence of provocation which would authorize a finding that the homicide was an act of voluntary manslaughter rather than murder. Duquette v. State, 265 Ga. 152, 153 (2) (454 SE2d 500) (1995).
9. McIntyre urges that the trial court erred in admitting hearsay testimony regarding statements made by Chapman after the termination of the conspiracy. However, the portions of the transcript wherein he contends that this occurred do not relate to the admission of any post-conspiracy statements attributed to Chapman. Instead, *12they relate to post-arrest drawings and writings attributed to McIntyre himself. Since this enumeration of error is not supported by the transcript, it is without merit.
Judgment affirmed.
All the Justices concur, except Fletcher, P. J., and Sears, J., who concur in part and dissent in part.The murder was committed on January 17,1988 and McIntyre was indicted on March 1, 1988. The guilty verdict was returned on June 10, 1988 and, on that same date, the judgment of conviction and sentence was entered thereon. The motion for new trial was filed on July 6, 1988 and denied on June 11, 1993. McIntyre’s motion for an out-of-time appeal was granted on January 4,1995. The notice of appeal was filed on January 12,1995 and the case was docketed in this Court on April 7, 1995. Oral argument was heard on June 26, 1995.