
109 Mich. App. 306 (1981)
311 N.W.2d 759
PEOPLE
v.
BUSCHARD.
Docket No. 49873.
Michigan Court of Appeals.
Decided September 9, 1981.
Frank J. Kelley, Attorney General, Robert A. Derengoski, Solicitor General, John A. Smietanka, Prosecuting Attorney, and Angela Baryames, Assistant Prosecuting Attorney, for the people.
Susan J. Smith, Assistant State Appellate Defender, for defendant on appeal.
Before: R.B. BURNS, P.J., and ALLEN and T. GILLESPIE,[*] JJ.
ALLEN, J.
Defendant was convicted by a jury of carrying a weapon in a motor vehicle, MCL 750.227; MSA 28.424. He also pleaded guilty to being a second time felony offender, MCL 769.10; MSA 28.1082. He was sentenced to three to seven and a half years in prison and appeals as of right.
On May 30, 1979, police officers, responding to a tip, stopped a car in which defendant was a passenger and asked for defendant by name. All three occupants offered identification and exited from the car. Police said defendant, the only passenger in the back seat, had been sitting on a .357 magnum revolver.
Sam Stueland, the front seat passenger, told police the gun was his. Defendant denied any knowledge of the gun, stating he was having severe chest pains and was oblivious to his surroundings. Defendant was arrested. The car's driver, Greg Shafer, and Stueland were allowed to leave, although they were later told they could be charged with carrying a weapon in a vehicle.
Both accomplices testified at trial pursuant to a plea agreement that allowed them to plead guilty *310 to a misdemeanor charge, as opposed to the felony with which defendant was charged. Stueland and Shafer testified that they came to Benton Harbor on May 30, 1979, on an amateur detective investigation, trying to find Stueland's stereo which had been stolen two weeks earlier. In so doing, they stopped at several bars. Stueland testified that he placed his gun in the car's trunk and both Stueland and Shafer testified that they did not see the gun again that evening until the police stopped the car.
Defendant testified that he was with Shafer and Stueland but denied having any knowledge of the gun. He testified that when the car was stopped by police he was having an angina attack and did not notice his surroundings.
On appeal defendant raises five issues, none of which was preserved for appellate review by an objection at the trial level. Failure to object at trial prevents the trial court from correcting any possible error and may result in the waste and delay of a new trial. Generally, failure to object precludes appellate review. We will nevertheless review defendant's claims of error to avoid manifest injustice. People v Provience, 103 Mich App 69, 72; 302 NW2d 330 (1981).
Defendant first argues that he was denied a fair trial when a police officer testified that an informant told him one passenger in the car in which defendant was riding was carrying a gun. The officer testified that early on May 30, 1979, he stopped a white 1967 Camaro. The prosecutor asked if he recalled why and the officer replied:
"I had received information from a street informant of a subject in the vehicle carrying a gun." *311 The officer said he asked the occupants for identification because he "was looking for a particular individual named Buschard". The informant did not testify at trial.
Defendant argues that this response constituted inadmissible hearsay. We cannot agree. Hearsay is an out-of-court statement offered to prove the truth of the matter asserted. MRE 801(c). When examined in its context, it is clear the question was asked as background to determine the motive for stopping the Shafer vehicle, not to prove the veracity of the informant's tip. People v Eady, 409 Mich 356, 361; 294 NW2d 202 (1980).
Even if the statement did not constitute inadmissible hearsay, it should not have been admitted unless relevant. People v Wilkins, 408 Mich 69; 288 NW2d 583 (1980). Evidence of an informant's tip could be admissible to demonstrate the police officer's motivation in stopping the car, if such motives were relevant to an issue in the case. Eady, supra, 361. In the case at bar, however, motivation was not an issue, nor can we find any other relevance to this information.
We also note that testimony about the undisclosed informant's tip violated defendant's Sixth Amendment right to confront the witnesses against him. People v Harris, 41 Mich App 389, 391; 200 NW2d 349 (1972).
We conclude that had defendant objected to the irrelevant testimony regarding the informant's tip, the trial court should have excluded it. We find, however, that admission of this evidence did not result in reversible error. In so doing, we recognize that a jury might infer from the informant's tip that defendant had knowledge of the gun. This knowledge was also established by the direct testimony of both accomplices and by defendant's proximity *312 to the gun when stopped by police. This unobjected to testimony was merely cumulative and did not result in manifest injustice.
Defendant next argues that the prosecution should have endorsed and produced the informant and other persons in the bar where defendant allegedly had the gun. Generally, the prosecution is required to endorse and produce at trial all res gestae witnesses. MCL 767.40; MSA 28.980. A res gestae witness is one "who was an eyewitness to some event in the continuum of a criminal transaction and whose testimony will aid in developing a full disclosure of the facts surrounding the alleged commission of the charged offense". People v Hadley, 67 Mich App 688, 690; 242 NW2d 32 (1976). A person need not be an actual eyewitness to be presumed to be a res gestae witness; it is enough that his or her testimony would aid in developing a full disclosure of the facts. People v Abdo, 81 Mich App 635, 643-644; 265 NW2d 779 (1978). It is possible that the bar patrons in the instant case may have been able to offer such information.
A defendant, however, bears the responsibility of moving for a hearing during trial, or for a new trial, before claiming on appeal that the prosecution has failed to endorse and produce a res gestae witness. People v LeFlore, 96 Mich App 557, 563-564; 293 NW2d 628 (1980). Failure to move for either will preclude appellate review unless manifest injustice will result. People v Pearson, 404 Mich 698, 723; 273 NW2d 856 (1979), LeFlore, supra.
We do not believe manifest injustice occurred in the present case. Even if the prosecution had produced bar patrons who testified that defendant carried no gun in the bar, their testimony would *313 have been consistent with that of defendant's accomplices, who said they did not see the gun after placing it in the car trunk. Moreover, defendant's knowledge of the gun was established by his proximity to the gun when the car was stopped by police. This fact was the basis of the prosecution's argument that defendant had knowledge of the gun; the testimony of the bar patrons could not have refuted this. We conclude that, even if the bar patrons were res gestae witnesses, defendant waived any error in their nonproduction.
Defendant next argues that he was denied a fair trial because the prosecutor introduced evidence that the accomplices promised to testify truthfully at defendant's trial in return for being charged with a misdemeanor firearm offense. Generally, the fact that a codefendant pleaded guilty is inadmissible as there is a danger that a jury will infer a defendant's guilt from that plea. Anno: Prejudicial effect of prosecuting attorney's argument or disclosure during trial that another defendant has been convicted or has pleaded guilty, 48 ALR2d 1016, People v Lytal, 96 Mich App 140, 159; 292 NW2d 498 (1980), lv gtd 409 Mich 923 (1980). The prosecution does have a duty to disclose promises made in return for testimony on a defendant's request or if false testimony is presented. People v Atkins, 397 Mich 163, 173; 243 NW2d 292 (1976). It is not necessarily reversible error for the prosecution to anticipate the cross-examination of an accomplice witness and raise the issue of an accomplice's plea bargain in direct examination. Lytal, supra, 157.
In the case at bar, the prosecution's questions went beyond mere disclosure of the fact that a plea agreement had been reached. Here the prosecutor asked each accomplice if he had agreed to *314 testify truthfully. No Michigan case has considered whether the disclosure of an agreement to testify truthfully is permissible.
Other jurisdictions are divided over whether such evidence constitutes reversible error. In United States v Koss, 506 F2d 1103 (CA 2, 1974), cert den sub nom Layne v United States, 420 US 997; 95 S Ct 1402; 43 L Ed 2d 657 (1975), the second circuit held that the text of a plea agreement, which included a provision that the accomplice would be liable for all crimes if he committed perjury, was admissible on redirect examination of an accomplice in order to rehabilitate the witness. In United States v Creamer, 555 F2d 612, 617-618 (CA 7, 1977), the seventh circuit rejected a defendant's argument that reference to an agreement to testify truthfully constituted impermissible prosecutorial vouching. The court found this was not an overt statement of personal belief in the witness's veracity, and found no error. In United States v Roberts, 618 F2d 530 (CA 9, 1980), the ninth circuit held that reference to a policeman sitting in the courtroom was impermissible when the prosecutor suggested the policeman was monitoring testimony to determine if a conspirator was testifying truthfully. In dicta, the court found that reference in argument to a promise to testify truthfully may be, but not necessarily is, error. The court suggested the application of a balancing test before admitting a plea agreement containing a reference to a promise of truthfulness.
"A strong case can be made for excluding a plea agreement promise of truthfulness. The witness, who would otherwise seem untrustworthy, may appear to have been compelled by the prosecutor's threats and promises to come forward and be truthful. The suggestion is that the prosecutor is forcing the truth from his *315 witness and the unspoken message is that the prosecutor knows what the truth is and is assuring its revelation.

* * *
"A trial court should be alert to the problem of vouching before admitting a plea agreement containing a promise to testify truthfully. The court should consider the phrasing and content of the promise to ascertain its implications and decide whether an instruction to the jury would dispel any improper suggestions.
"USING THE PROMISE IN ARGUMENT
"In addressing the third issue we consider the use which a prosecutor may make of a promise to testify truthfully once a plea agreement has been admitted.
"The prosecutor may not tell the jury that the government has confirmed a witness's credibility before using him. Gradsky v United States, supra. He should be no more able to indicate that the government has taken steps to compel the witness to be truthful. Both of these arguments involve improper vouching because they invite the jury to rely on the government's assessment that the witness is testifying truthfully." Roberts, supra, 536.
The most recent relevant case is United States v Hedman, 630 F2d 1184 (CA 7, 1980). Defendants challenged the admissibility of testimony elicited by the government on direct examination of three company employees that they had been granted immunity. Defendants claimed that the testimony was inadmissible because it was used to enhance the credibility of the witnesses. The court rejected the argument saying:
"`We find nothing improper about the question of the witness' understanding of the terms of the immunity order in this case. There was no insinuation by the prosecutor, direct or otherwise, that the government possessed knowledge to the exclusion of the jury on the issue of the immunized witness' veracity. Cf. United *316 States v Creamer, 355 F2d 612 (CA 7, 1977). Further, we believe that the jury's function of assessing credibility and weighing testimony is aided by evidence of an immunized witness' understanding of the terms under which he or she is testifying. Indeed, such questions by the prosecution frequently provide a convenient opening for more exploration of a fertile area on cross-examination.' [United States v Craig, 573 F2d 513, 519 (CA 7, 1978)]. We are aware of no persuasive authority to the contrary. The testimony concerning immunity in this case fails to reflect an implication that the government possessed knowledge to the exclusion of the jury on the issue of the immunized witnesses' veracity. Moreover, the trial court instructed the jury that the credibility of the immunized witnesses was susceptible to special scrutiny." Hedman, supra, 1198. (Emphasis supplied.)
Based upon the state and federal decision cited above, we cannot hold that any reference to a plea agreement containing a promise of truthfulness is in itself grounds for reversal. A more accurate statement of the law appears to be that, although such agreements should be admitted with great caution, admissibility of such an agreement is not necessarily error unless it is used by the prosecution to suggest that the government had some special knowledge, not known to the jury, that the witness was testifying truthfully. In this connection, we note that Roberts, supra, was a much stronger case for the defendant than the situation in the case at bar. Roberts contained testimony of both an agreement to testify truthfully and in addition, over objection of defense counsel, testimony that the government had a detective sitting in court auditing the witness's testimony to insure its truthfulness. It was this latter testimony, and not the fact that the agreement contained the promise to testify truthfully, that caused the Roberts *317 court to reverse.[1] Accordingly, we conclude that it is not the testimony that the accomplices agreed to testify truthfully that would constitute error in the instant case. The only question is whether the prosecution's use of such testimony constitutes grounds for reversal.
In his closing argument to the jury, the prosecutor made no reference to the plea agreement. However, the prosecutor made the following remarks, the emphasized portions of which defendant claims constitute error:
"The judge will instruct you with regard to accomplices' testimony, and that is what Mr. Shafer and Mr. Stueland really are, they are accomplices to carrying that gun in the car, you should judge their testimony carefully. That is obvious to you, I am sure, if a person is promised something in exchange for testifying or if they tell it in such a way that they obviously have a motive for keeping their own involvement down and playing up somebody else's involvement, that should be judged. But I submit to you in this case it is not the case. The men have been very candid. They have admitted they were possessing or carrying a pistol in the car. In fact, Mr. Stueland and Mr. Shafer, what reason would they have for saying as they did that they didn't put that gun anywhere but in the trunk, and that Mr. Buschard was involved in putting it in the passenger compartment and getting it underneath himself when they were stopped. If you will, their motive, if they wanted to  I mean what would they have? They have already admitted it. If it was the truth, that they somehow put it in there and as Mr. Banyon alleges, then it would be easier for them to say, yes, I put it in there. It doesn't make any difference for their purposes that it is in the trunk or the passenger compartment or *318 wherever. But they are telling you the way it happened because that is all they know about it.
"Now, they are going to testify that they have been allowed to plead to a misdemeanor. That you may consider also. But, that alone. They have been promised nothing about the sentence and they have testified before you here today. I submit to you when you take their testimony coupled with the officers' testimony, the exhibits and all of the testimony, that it together with all of it should indicate to you that the defendant should be held accountable for the crime which he is charged and that he denies he has any involvement with." (Emphasis supplied.)
We disagree on four grounds. First, in the case at bar no objection to the prosecutor's argument was made and a curative instruction was not requested. Second, the prosecution made no reference to steps taken by the prosecution to insure that the witness would testify truthfully. Third, the trial judge did instruct the jury that the testimony of accomplices should be viewed with skepticism. That instruction was not brief or casual but consisted of more than one page of transcript and included a statement that the jury should consider whether the accomplices testified falsely in order to place guilt upon the defendant.[2] Fourth, read in its entirety the statement appears to be a statement of the prosecutor's conclusion that the accomplices' testimony "coupled with the *319 officers' testimony, the exhibits and all the testimony, that it together" should indicate the defendant's guilt of the crime charged. We do not find such a statement impermissible vouching. We further find that any prejudice which might have resulted could easily have been eliminated had a curative instruction been requested. Finally, we note that at the time of trial the decision in Roberts, supra, had not been announced,[3] and consequently the trial court was without benefit of its admonitions.
Defendant raises two additional arguments which we address briefly. Defendant maintains that inadequate evidence was presented at the preliminary examination to warrant the magistrate's decision to bind over on the charged offense. Any error that may have occurred in binding over was waived, as defendant filed no motion to quash. People v Miller, 62 Mich App 495; 233 NW2d 629 (1975). Moreover, we find that ample evidence of defendant's knowledge of the gun was presented, as the police testified at the preliminary examination that the defendant was sitting on the gun when arrested. This information was adequate to establish that the offense had been committed and there was probable cause to believe that the defendant had committed it. Guilty knowledge could be inferred from defendant's apparent attempt to conceal the gun. People v Beets, 105 Mich App 350; 306 NW2d 508 (1981). The magistrate did not abuse his discretion in binding defendant over for trial.
Finally, defendant argues that the stop of Shafer's car and the arrest of defendant violated defendant's Fourth Amendment protection against unreasonable *320 searches and seizures. We believe that the investigatory stop of the automobile was reasonable, based on the informant's tip, which was verified by police observation. People v Whalen, 390 Mich 672, 682; 213 NW2d 116 (1973). Once the car was properly stopped, police observed a gun in plain view where defendant had been sitting. This provided probable cause for his arrest. There was no error in the initial stop or in defendant's arrest.
Affirmed.
NOTES
[*]  Circuit judge, sitting on the Court of Appeals by assignment.
[1]  "This court held [in United States v Roberts, 618 F2d 530 (CA 9, 1980)] that the prosecutor committed reversible error when, over an objection sustained by the court, he attempted to bolster the credibility of the chief prosecution witness with evidence outside the record." United States v Roberts, 640 F2d 225, 226 (CA 9, 1981).
[2]  "You may consider whether the testimony was affected by either of them being granted immunity from punishment or from receiving a promise of leniency or being allowed to plead guilty to a lesser offense. You may consider whether the testimony is falsely slanted in such a way as to place guilt upon the defendant in order to further the witness' own interest or any other bias or motive which may have prompted or induced the witness in his testimony. You should also consider how each of those witnesses impressed you with his appearance upon the witness stand. And so to summarize, you should examine an accomplice's testimony with greater care than you would use to examine the testimony of an ordinary witness. It should be carefully and closely examined before a conviction is based upon it."
[3]  Defendant was convicted September 11, 1979, and Roberts was decided May 7, 1980.
