James Draper was convicted of first degree robbery, § 569.020, RSMo 1978, and sentenced to eighteen years in prison. The Western District Court of Appeals reversed his conviction and remanded the case for a new trial. A dissenting judge deemed the majority opinion to be in conflict with State v. Smith, 649 S.W.2d 417 (Mo. banc 1983), and State v. Harrell, 637 S.W.2d 752 (Mo.App.1982), and certified the cause to this Court pursuant to Mo. Const, art. Y, § 10. We reverse the trial court’s judgment and remand the cause for a new trial.
On August 17, 1982, at approximately 7:15 p.m., Manuel Gomez was robbed outside a grocery store as he was putting his groceries into his car. A man carrying a knife asked him for his billfold. Upon dis*864covering that the billfold contained no money, he searched the victim and asked for all the money in his pockets. After receiving only $3 and some change, he searched Gomez further, and on finding nothing, walked away.
Gomez saw the robber twice, glancing at him during the robbery and observing him walking into the store in the rear view mirror after the robbery. Daylight permitted him to see a black male with a beard wearing a tan cap, white T-shirt and jeans.
A few blocks away, Gomez flagged down a police officer, and -gave him a description of his assailant and of the knife used in the robbery. The officer arrived on the scene in his patrol car, with Gomez following approximately five minutes after the attack.
According to Gomez, when the police ear drove up, defendant was walking up the street from the grocery store; when he saw the police officer, he stooped down and started talking to some men. The police officer testified that when he first saw defendant, defendant was starting to walk northward from the store, that when he saw the police officer he started walking fast, and that when the officer pulled over to him he went to two or three men and began talking with them. The officer concluded, “He was trying to elude me.”
Gomez identified defendant as the robber, and the officer arrested him. Upon searching him, the officer found a butcher knife with a chip on the handle identical to that described by Gomez, and $3 and some change.
Defendant testified that he did not commit the robbery. He claimed he found the knife on his way to the store, that before reaching the store he met some friends, and that he stopped to talk and drink with them. He explained his furtive movements by stating that he was partly drunk at the time, and that when he saw the police officer he panicked and attempted to get rid of the bottle before the officer walked over to him.
The only issue on appeal is whether the trial court erred in overruling defendant’s challenge for cause of Venireman Carol Martin.
Early in the voir dire, the prosecutor asked the following general questions to which no one on the panel responded:
Now the Judge will instruct you, ladies and gentlemen, as to the credibility of witnesses and how you are to read and decide the credibility of any witness. Is there anyone who would be unable to follow that instruction merely because the witness may be a police officer? Is there anyone who would be likely to give less credibility to testimony because that person testifying is a police officer?
Later, Venireman Martin stated that a close personal friend was a police officer. The following exchange then took place between Martin and defense counsel:
MR. O’BRIEN: All right, and is there anything about your relationship with this gentleman, having known him, that would cause you to more than likely believe a police officer?
VENIREMAN MARTIN: I think it might.
MR. O’BRIEN: Would you have difficulty not believing a police officer or difficulty in your own mind arriving at a conclusion that a police officer might lie?
VENIREMAN MARTIN: I don’t understand the—
MR. O’BRIEN: Well, let me ask you this. Could you in your own mind accept the fact that it’s possible for a police officer to come in and say something that isn’t true?
VENIREMAN MARTIN: I don’t think so.
THE COURT: I didn’t hear her response.
VENIREMAN MARTIN: I don’t believe so.
Martin later stated in response to other individual questioning that she would be able to follow the court’s instructions concerning defendant’s right not to testify on his own behalf. Toward the end of voir dire, the panel was asked if anyone for any *865reason thought he or she should not serve on the jury for any particular reason. No one responded.
Defendant challenged Martin for cause. The trial court denied the challenge, stating, mistakenly, that Martin later indicated she could be a fair and impartial juror. Defendant exercised one of his peremptory challenges to eliminate her, and Martin did not sit on the jury.
A defendant in a criminal case is entitled to a panel of qualified jurors before he is required to make his peremptory challenges. State v. Lovell, 506 S.W.2d 441, 443 (Mo. banc 1974); State v. Land, 478 S.W.2d 290, 292 (Mo.1972). When a venireman expresses a partiality toward police officer testimony per se — as a generic class — the bias of credibility contrary to the interest of the complainant-litigant disqualifies service as a juror. State v. Williams, 643 S.W.2d 832, 834 (Mo.App.1982); State v. Owens, 620 S.W.2d 448, 450 (Mo.App.1981). The trial court is accorded wide discretion in ruling on challenges for cause, but also has a duty to evaluate closely, and at times independently examine, the qualifications of potential jurors. Lovell, supra at 444; State v. Ealy, 624 S.W.2d 490, 493 (Mo.App.1981). Without such independent examination, a more searching review by the appellate court is justified. State v. Butler, 660 S.W.2d 225, 227 (Mo.App.1983); Williams, supra, at 834; Ealy, supra, at 493; State v. Holliman, 529 S.W.2d 932, 939 (Mo.App.1975). The trial court’s determination, however, will be rejected only upon a clear showing of abuse of discretion. State v. Olinghouse, 605 S.W.2d 58, 69 (Mo. banc 1980).
No clear line can be drawn as to when a challenge for cause should or should not be sustained; each case must be judged on its particular facts. Smith, supra, at 422; State v. Cuckovich, 485 S.W.2d 16, 22-23 (Mo. banc 1972); State v. Harris, 425 S.W.2d 148, 155 (Mo.1968). Although errors in the exclusion of potential jurors should always be on the side of caution, Butler, supra, at 227; State v. Carter, 544 S.W.2d 334, 338 (Mo.App.1976); reversal is required only if the defendant has been prejudiced. Butler, supra, at 227; Harrell, supra, at 757. The defendant has been held not to be prejudiced where the police officer did not provide any elements of the State’s case. Butler, supra, at 227; Harrell, supra, at 757; where the more important evidence came from other witnesses, Cuckovich, supra, at 23; State v. Daniels, 629 S.W.2d 627, 630 (Mo.App.1982); and where the police officer did not testify to any truly contested issue. Smith, supra, at 424.
In this case, although Martin indicated she would accord police testimony greater weight than that of other witnesses, she was never individually questioned further by the court or counsel concerning that matter. No further questioning displayed an ability on her part to evaluate all testimony by the same standard. See Harrell, supra, at 756. The only other matter on which she was individually questioned was unrelated, concerning defendant’s right not to testify on his own behalf. The trial court’s own response to counsel’s motion to strike Martin indicated that it had confused the two incidents, incorrectly attributing her assertion that she could follow the court’s instructions as to defendant’s right not to testify to the questioning concerning police testimony. Neither Martin nor any other member of the venire panel responded to general questions concerning their ability to follow the court’s instructions concerning the credibility of witnesses, particularly police officers, or their ability to serve on the jury for any unspecified reason. However, such lack of response to general questions is not conclusive on the issue of bias, particularly as the juror’s own conclusions in this regard are not dispositive. Lovell, supra, at 444, Carter, supra, at 337. Under the circumstances of this case, the court erred in failing to strike Martin for cause. In addition, the trial court’s error was prejudicial in this case. Although the testimony of the victim alone established all the elements of the State’s case, the testimony of the police officer as to defendant’s behavior indicated *866a consciousness of guilt of the robbery and contested the alibi of the defendant. Under such circumstances reversal is warranted.
Our holding is consistent with Smith, supra, and Harrell, supra. In Smith, unlike this case, the venireman was questioned at length by the trial judge, and stated he would treat policemen no differently than other witnesses in determining their credibility. 649 S.W.2d at 424. Moreover, there the police officers did not testify to any truly contested issue. Id. In Harrell, the entire voir dire did not indicate an improper preference toward police testimony, and police testimony was of only relatively minor importance. 637 S.W.2d at 757. Here there was no questioning by the court, the entire voir dire does not show Martin to be unbiased, and the police testimony was important in contradicting defendant’s alibi.
The judgment is reversed and the cause is remanded for a new trial.
WELLIVER, HIGGINS, and BILLINGS, JJ., concur. GUNN, J., dissents. RENDLEN, C.J., dissents in separate opinion filed. BLACKMAR, J., dissents in separate opinion filed and concurs in dissenting opinion of RENDLEN, C.J.