Appellant was convicted of carnal knowledge of a nine-year-old child, following reversal of a prior conviction by this court.1 The points raised on this appeal concern the admissibility of certain medical testimony and the necessity of certain instructions.
The first question is whether the trial court erred in admitting the testimony of an expert witness who admittedly had no independent recollection of the facts to which he testified,2 but who testified after reviewing his testimony recorded at the first trial. Appellant claims the testimony is inadmissible as not meeting the standards of either “present recollection revived” or “past recollection recorded”, and that prejudice resulted from the impossibility of cross-examining the witness effectively.
The challenged testimony involves conclusions that appellant was mentally competent at the time of the crime, based on mental examinations of appellant made by the witness in August and September of 1949. The first trial, the record of which formed the basis of the witness’ present testimony, occurred in early February of 1950.
The effect of the witness’ testimony in the circumstances of this case was to introduce in evidence the substance of his testimony as recorded at the first trial. “Whether the record is directly admitted into evidence, or indirectly by the permissive parroting of the witness, it is nevertheless a substitute for his memory and is offered for the truth of its contents.” United States v. Riccardi, 3 Cir., 1949, 174 F.2d 883, 887.
There is no doubt that had the witness been legally unavailable his former testimony would have been admissible and could have been proved by the stenographic transcript of the first trial. Cf. Meyers v. United States, 1948, 84 U.S.App.D.C. 101, 171 F.2d 800, 11 A.L.R.2d 1, certiorari denied, 1949, 336 U.S. 912, 69 S.Ct. 602, 93 L.Ed. 1076. Court reporters are officials appointed by the court under authority of statute for the purpose of preserving testimony, and their transcripts, by statute,3 “shall be deemed prima facie a correct statement of the testimony taken. * * * ” 4
Nor should it be disputed that a judicial transcript is the proper subject for a record of past recollection.5 Courts have long acknowledged the propriety of a witness adopting a recollection recorded in the past where his once existing recollection has vanished. The chief difficulty precluding the use of past recorded recollection has been the need to insure “the accuracy and identity of the record,” i. e., that the memorandum or document reflects the witness’ past recollection. 3 Wigmore, Evidence 64 (3d ed.1940). To this end courts have formulated rules designed to guarantee that the recorded knowledge was clearly and accurately remembered by the witness when the record was made or verified. United States v. Riccardi, supra. If these requirements of reliability are met, the nature of the record as well as the mode of its preparation should be immaterial.
The use of a judicial transcript recorded by an official court reporter at a time when the events to which the wit*132ness testified were fairly fresh in his mind satisfies the essential tests of reliability. Keeping in mind that the rules governing the use of past recorded recollection were developed “to secure the best available memory of the witness, while guarding against imposition by false use of purporting memoranda,” 6 we are not willing to say that the trial judge abused his discretion in admitting this testimony. Cf. United States v. Socony-Vacuum Oil Co., 1940, 310 U.S. 150, 231-7, 237, 60 S.Ct. 811, 84 L.Ed. 1129.
In the present case the witness reviewed the transcript before the trial. Perhaps a more orderly judicial procedure in this situation would recommend that the witness produce and use the transcript while testifying.7 It appears from this record, however, that appellant did not question the authenticity of the document which the witness reviewed and, being a matter of public record, the transcript was at all times available to appellant. Thus appellant had an opportunity to check the verity of the testimony against the transcript and direct attention to discrepancies. Furthermore, the witness was in fact cross-examined extensively at the second trial concerning his medical opinion formulated from the 1949 examinations; any limitation of the effectiveness of this cross-examination was at least partially cured by the opportunity afforded appellant for cross-examination at the first trial. See Mattox v. United States, 1895, 156 U.S. 237, 15 S.Ct. 337, 39 L.Ed. 409. In these circumstances we do not find prejudice resulting from the procedure followed in the trial court.
Appellant also urges the trial court committed reversible error in failing to charge the jury that if appellant should b.e acquitted by reason of insanity he would be sent to a mental institution for as long as his safety and that of the public require. Appellant contends that under Taylor v. United States8 such a charge was mandatory whenever insanity is a defense.9
The Taylor case did not make such an instruction mandatory in the sense that in all circumstances its omission is reversible error. We need not interpret the precise effect of the language there used, for this instruction, like others, is subject to Rule 30.10 We must look, then, to *133see whether manifest injustice resulted from the omission.
The record in this case shows that defense counsel did not request the court to so instruct the jury. Following the judge’s charge, the United States Attorney raised the issue of the possible application of the Taylor ease. The trial judge indicated he did not regard the instruction as mandatory. Defense counsel neither urged that it be given nor objected to its omission. The defendant having thus consciously and deliberately refrained from asking for the instruction and similarly having failed to object to its omission, he will not be heard to complain of it now, seven years after the offense and six years after his first trial. Considering the entire record, we do not believe the omission of this instruction so prejudiced the appellant’s substantial rights as to deprive him of a fair trial.
The judgment below is therefore
Affirmed.
. Tatum v. United States, 1951, 88 U.S.App.D.C. 386, 190 F.2d 612.
. Upon cross-examination the witness admitted that his present recollection consisted solely of a present recognition of appellant and the fact that he had examined him in the past.
. 28 U.S.C. § 753(b) (1952).
. Wigmore advocated the acceptance of former testimony whenever the witness was presently unable to testify, even where lapse of time was responsible for the loss of present recollection. 5 Wig-more, Evidence § 1408 (3d ed.1940).
. We note a paucity of authority on this point. See cases cited at 125 A.L.R. 246 (1940).
. 3 Wigmore, Evidence 100 (3d ed.1940).
. It has been held, however, that the production in court of the memorandum of past recollection is not an essential prerequisite to the admission of the testimony. Loose v. State, 1903, 120 Wis. 115, 97 N.W. 526.
. 1955, 95 U.S.App.D.C. 373, 222 F.2d 398, 404. In this case the court stated: “But we think that when an accused person has pleaded insanity, counsel may and the judge should inform the jury that if he is acquitted by reason of insanity he will be presumed to be insane and may be confined in a ‘hospital for the insane’ as long as ‘the public safety and * * * [his] welfare’ require.” (Footnotes omitted). Id. at page 379, 222 F.2d at page 404. The omission of this instruction, however, was not made a ground of reversal in Taylor. Ibid. See also Durham v. United States, 1956, 99 U.S.App.D.C. 132, 237 F.2d 760; Kelley v. United States, 1956, 99 U.S.App.D.C. 13, 236 F.2d 746.
. In Lyles v. United States, 1957,-U.S. App.D.C.-, --F.2d-, we made such an instruction mandatory prospectively from that decision.
. Rule 30, Fed.R.Crim.P., 18 U.S.C., provides in part; “No party may assign as error any portion of the charge or omission therefrom unless he objects thereto before the jury retires to consider its verdict, stating distinctly the matter to which he objects and the grounds of his objection.” The complaining witness was 9 years old when the offense occurred in 1949. One purpose of Rule 30 was to preclude a defendant from exploiting his own failure to make timely objections. In this case there is not even a basis for suggesting the failure was an oversight of counsel.
To encourage, or even tolerate this one-sided “Russian Roulette” with the courts could lead to a breakdown of all law enforcement in a system already plagued by multiple trials. Tatum’s next plea, if we gave him one, could well be that he has been denied a speedy trial. See Williams v. United States, 1957, 102 U.S.App.D.C.-, 250 F.2d 19.