OPINION
ZLAKET, Justice.Carl Dean Johnson was charged with two counts of aggravated assault and one count of first degree burglary. On the opening day of trial, the judge preliminarily instructed the jury that defendant was innocent until proven guilty beyond a reasonable doubt. The presentation of evidence took the rest of that day. On the next day, the lawyers gave closing arguments, in which both reiterated the state’s burden of proof.
The trial judge then delivered additional jury instructions, but did not repeat those previously given. She did not reinstruct on the state’s burden of proof. Neither counsel requested reinstruction or objected to the court’s failure to do so. In a bench conference, however, the prosecutor asked *275for modification of the special form of verdict to advise the jurors that the allegation of “dangerousness” had to be proven beyond a reasonable doubt. The judge responded by immediately giving the jury the following oral charge, which had neither been prepared in writing nor approved by counsel in advance—a practice we do not condone for obvious reasons:
THE COURT: I want to make it perfectly clear that your decision of guilty or not guilty must be based upon your conviction beyond a reasonable doubt, whatever that conviction is.
If on any count you find the defendant guilty, then your determination as to whether the allegation of dangerousness is true or not true must also be beyond a reasonable doubt.
(Emphasis added.) Neither counsel objected. A written copy of the instructions, including those read at the beginning of trial, but excluding the foregoing extemporaneous oral charge, was given to the jurors for use in their deliberations.
Defendant was convicted on all counts, and thereafter was sentenced to consecutive prison terms of ten and one-half years on the burglary count, and fifteen years on each of the aggravated assault counts. The court of appeals affirmed the convictions, with one judge strongly dissenting. State v. Johnson, 169 Ariz. 567, 821 P.2d 228 (Ct.App.1991). We granted review because we believe that the failure to reinstruct the jury at the close of the case on basic legal principles vital to defendant’s rights, when coupled with the erroneous burden of proof instruction given just before the jury began deliberations, mandates a new trial. We have jurisdiction pursuant to Ariz. Const. art. 6, § 5(3), and A.R.S. § 13-4035.
In the past nine years, this court and the court of appeals have published four separate opinions stating the importance of reinstructing a jury on the burden of proof at the close of a case. Each of those opinions involved the same trial judge as the instant case. In State v. Marquez, 135 Ariz. 316, 660 P.2d 1243 (Ct.App.1983), the court of appeals held that failure to reinstruct on the burden of proof after a defendant’s request is reversible error, stating:
In order that there be no further confusion, we hold that the preliminary instruction of the jury, authorized by Rule 18.6(c), Rules of Criminal Procedure, is for the purpose of preparing the jury for the trial and constitutes an orientation process by which the jury is made to understand its duties and responsibilities. Where elementary legal principles that will govern the proceedings are given to the jury as a part of the orientation, the trial judge must repeat all such legal principles in its charge to the jury, where such legal principles include matters of law vital to the rights of a defendant.
Id. at 322, 660 P.2d at 1249 (emphasis added).
That same year, in State v. Jackson, 139 Ariz. 213, 677 P.2d 1321 (Ct.App.1983), the court of appeals again stated that this judge’s failure to reinstruct the jury was error. The court held, however, that absent a party’s request for reinstruction, the error was not reversible where the trial lasted only one day and the jury had received preliminary instructions. 139 Ariz. at 217, 677 P.2d at 1325.
This court addressed the issue the following year in State v. Kinkade, 140 Ariz. 91, 680 P.2d 801 (1984), where the trial judge failed to reinstruct the jury on the burden of proof, but neither the state nor the defense objected. The court held it was error not to reinstruct, but the error was not “fundamental” under the facts of that case. 140 Ariz. at 94, 680 P.2d at 804. The jury had been instructed on reasonable doubt at the beginning of trial, took a copy of the instructions into the jury room, and the lawyers reiterated the burden of proof in closing argument. It did not appear to this court that the jurors’ understanding of the state’s burden had been compromised, and thus the failure to object was deemed a waiver.
We again faced the issue in State v. Jackson, 144 Ariz. 53, 695 P.2d 742 (1985), where defendant requested reinstruction on the burden of proof, but the judge re*276fused. Defendant thereafter objected. This court held once more it was error not to reinstruct, but did not reverse because “we can say beyond a reasonable doubt that the failure to instruct at the end of the trial did not influence the verdict of the jury.” 144 Ariz. at 55, 695 P.2d at 744. The court noted that the trial had been brief, the jurors were provided with written copies of the instructions, and counsel in final argument discussed the burden of proof charge previously given. Id. at 54, 695 P.2d at 743.
We are again compelled to address this issue, which long ago should have been put to rest. That only one of the above cases resulted in reversal should not have obscured their message. We say once more, without equivocation, that judges must instruct juries on basic legal principles, including burden of proof and reasonable doubt, following the evidence and before the commencement of deliberations. This is so even though a jury has been instructed prior to the presentation of evidence, and regardless of the brevity of the trial. The failure to reinstruct on such important matters at the conclusion of a case is error, as has been repeatedly stated for the past nine years. This error is not necessarily obviated by furnishing written copies of instructions to jurors, or by the fact that lawyers have argued the instructions in summation.
Common sense and experience tell us that jurors give special credence to the pronouncements of judges. Preliminary instructions prepare a jury for trial and constitute an orientation by which the jury is made to understand its duties and responsibilities. Marquez, 135 Ariz. at 322, 660 P.2d at 1249. Instructions given just before the jury deliberates will likely make more of an impression than those given prior to the presentation of evidence. Jackson, 144 Ariz. at 54, 695 P.2d at 743. A few extra minutes to reinstruct on basic legal principles is the modest cost of this additional safeguard to the rights of an accused.
By our decision today, we do not overrule prior case law holding that the failure to reinstruct is an error which can be waived. The inquiry in each case must necessarily be fact specific. Here, the failure to reinstruct is reversible because it was combined with the giving of a clearly erroneous instruction just before the jury began its deliberations. The last burden of proof instruction the jurors heard told them, in part, “your decision of guilty or not guilty must be based upon your conviction beyond a reasonable doubt.” That instruction improperly shifted the burden to the defendant to prove his innocence beyond a reasonable doubt. See State v. Hunter, 142 Ariz. 88, 90, 688 P.2d 980, 982 (1984) (holding it was fundamental error to give jury instructions improperly shifting the burden of proof to the defense); and State v. Mincey, 130 Ariz. 389, 398, 636 P.2d 637, 646 (1981), cert. denied, 455 U.S. 1003, 102 S.Ct. 1638, 71 L.Ed.2d 871 (1982) (same). We cannot now say beyond a reasonable doubt that the verdict was unaffected. See State v. McVay, 127 Ariz. 450, 453, 622 P.2d 9, 12 (1980).
Even where evidence of guilt appears overwhelming, we have an obligation to ensure that the judicial process is properly accomplished. We are charged under Art. 6, § 3 of the Arizona Constitution with administrative supervisory responsibility over the courts of this state, and we are unable to sit idly by while prescribed judicial procedures are ignored out of personal preference or convenience, or for any other unjustifiable cause. There is no suggestion in this record that the trial judge had a valid reason for ignoring the legal precedents previously recounted.
Our dissenting colleagues argue that because the trial appears to them to have been “fair,” the lower court’s errors should be overlooked. This “no harm, no foul” analysis sends the wrong message here. It ignores the fact that the integrity of the process by which human beings are incarcerated, or worse, is at least as important as the result in any particular case. A judicial system solidly grounded in rules of law protects citizens from the whims of those in power, including judges. Thus, contrary to the suggestion contained in one *277of the dissents, there is a legitimate goal to be served by ensuring that trials are conducted in accordance with settled legal principles and procedures. Though striving for that goal might exact the price of an occasional reversal, history teaches us the price is worth paying. The error below was not merely “technical,” as the dissent claims, nor is our decision today the result of anything so trivial as “frustration with a trial judge.” The instruction given was clearly wrong. More importantly, it was contrary to the presumption of innocence that stands among the basic foundations of the American criminal justice system. No legal principle has greater significance in a criminal trial.
As to the court’s failure to reinstruct, the procedural rules cited by one of the dissents could not have bestowed upon the trial judge discretion to ignore the clear pronouncements of four prior appellate decisions, unless we are prepared to abandon altogether the doctrine of stare decisis. Although the state conceded at oral argument that it would likely have been futile to request this judge to correct the erroneous instruction, or to reinstruct on the presumption of innocence, we do not condone the failure of the lawyers to have made proper and timely objections. Nonetheless, we cannot excuse the judge for having failed to carry out her clear responsibilities under the law, especially where human liberty was at stake. Numerous published decisions left no doubt as to the nature of those responsibilities with respect to jury reinstruction.
The opinion of the court of appeals is vacated. The convictions and sentences are reversed. The matter is remanded for a new trial.