UNITED STATES OF AMERICA, PLAINTIFF-APPELLEE,

v.

GEORGE POINDEXTER, MONTEZ DAY, DEFENDANTS-APPELLANTS

RYAN, Circuit Judge.

George Poindexter and Montez Day appeal their jury convictions for possession with intent to distribute cocaine and use of a firearm in a drug trafficking crime. Po-indexter also appeals his conviction of being a felon in possession of a firearm, although he makes no argument in support thereof.

Day raises the following issues:

1.Whether Day was unfairly prejudiced by the district court’s admonishment to defense counsel not to comment during closing argument on the lack of fingerprint evidence; and

2.Whether the district court erred by denying Day’s Fed.R.Crim.P. 29 motion for acquittal or a new trial based on the insufficiency of the evidence on Count II, the gun possession charge?

We conclude that the court abused its discretion in forbidding Day’s counsel to argue the lack of fingerprint evidence, and that Day was, as a result, denied a fair trial. We shall, therefore, reverse Day’s conviction on both counts.

Poindexter raises the following issues:

1. Whether Poindexter was unfairly prejudiced by the district court’s ruling limiting defense counsel’s opening statement;

2. Whether Poindexter was unfairly prejudiced by the district court’s ruling limiting cross-examination;

3. Whether the district court erred in explaining to the jury why it was being instructed to disregard a prior statement by the defendant; and

4. Whether Poindexter was unfairly prejudiced by the district court’s admonishment to codefendant Day’s counsel not to comment during closing argument on the lack of fingerprint evidence?

We think Poindexter was not unfairly prejudiced by any of the district court’s rulings. Although we believe the court abused its discretion in limiting closing argument, in light of the strong evidence of Poindexter’s guilt we find this error was harmless. We shall, therefore, affirm Po-indexter’s conviction.

I.

Belinda Sellers, who resided on Los An-geles Street in Memphis, Tennessee, observed drug sales and gun use at 766 Los Angeles Street, Memphis, Tennessee, the home of defendants George Poindexter and Montez Day. After she reported what she had seen to the police, she was asked to make a controlled purchase of narcotics and agreed to do so. With money supplied to her by the police, Sellers went to the defendants’ home to make a drug buy where she met Poindexter and a man named Tarmooney. While inside the house, Sellers observed a “brick” of cocaine “the size of a paper towel.” Poindex-ter and Tarmooney took Sellers’ money and told her they needed a scale to weigh the cocaine. They left the room and returned about fifteen minutes later with a package of cocaine which they sold to Sellers. Based on this information, the police obtained a warrant to search the home.

The police officers who conducted the search testified that upon arriving at the home on January 5, 1990, to serve the warrant, they knocked at the door and yelled “police.” There was no response, but when one of the officers heard shuffling inside, Officer Ross hit the door with a battering ram. On the second try, the door flew open. As the police entered, Poindexter fired a shot which struck Officer Robert Vaughn in the shoulder. The officers immediately arrested Poindexter. During the search that followed, the police discovered sixteen grams of cocaine in the false bottom of a shaving cream can found in the bathroom. They also found three guns: a nine millimeter pistol in the front bedroom; a .32 caliber pistol on a lamp stand in the front room, and a .22 caliber pistol, the weapon used by Poindex-ter to shoot Vaughn. The police discovered Montez Day and a female visitor hiding in the closet of the rear bedroom.

Both Poindexter and Day were indicted on charges of possession of approximately sixteen grams of cocaine with intent to distribute, in violation of 21 U.S.C. § 841(a)(1) (Count I), and knowingly carrying or using a firearm during and in relation to a drug trafficking crime, in violation of 18 U.S.C. § 924(c) (Count II). Additionally, Poindexter was charged with knowing possession of a firearm by a convicted felon, in violation of 18 U.S.C. § 922(g) (Count III). The defendants were tried by a jury in a joint trial.

During his opening statement, defense counsel attempted to explain that Poindex-ter used the gun in self-defense, and not in relation to a drug trafficking crime. The court refused to permit this claim, stating that self-defense is not relevant to a charge of using or carrying a firearm in relation to a drug trafficking crime.

During the government’s case in chief, Sellers admitted, under cross-examination by Day’s counsel, that she used crack cocaine approximately once a month over a four-month period. Counsel then attempted to impeach Sellers’ veracity by referring to testimony she had given at a prior hearing in which she stated that she did not then recall using drugs. The prior testimony had begun with the question whether there was any reason Sellers would have trouble recalling dates. She was then asked whether she had trouble recalling because she used drugs. The court sustained the government’s objection to this impeachment effort on the ground that defense counsel’s cross-examination questions lifted the prior testimony out of context and were misleading and confusing.

On further cross-examination, Sellers, in response to an inquiry about how much cocaine she had purchased from Poindex-ter, answered that she had purchased an “eight ball.” She stated that she did not know how many grams were in an eight ball but that she had turned over her entire purchase to the police. Later, defense counsel asked Officer Balee how much cocaine was in an eight ball and the officer responded that an eight ball is an eighth of an ounce, or 3.5 grams. The court sustained the government’s objection when counsel asked the officer to convert the amount to grams. As an offer of proof, Officer Balee testified that Sellers turned over to the police only .8 grams. At a bench conference, defense counsel claimed that this line of questioning was relevant to Sellers’ credibility since she had testified that she bought an eight ball, 3.5 grams, but turned over to the police only .8 grams. The court prohibited the questioning, however, because there was no evidence that Sellers knew how much an eight ball weighed. Stephanie Simmons, Poindexter’s girlfriend who was present during the raid, also testified. At a prior hearing in juvenile court, Simmons had testified that on the night of the raid the defendants “were talking about how much an ounce would cost and stuff like that and who would want to buy, and he going to hook them up with some people.” At trial, Simmons denied ever having heard such a discussion. When confronted with her prior statement, she acknowledged having given it. Simmons also testified that the two defendants carried guns with them “all the time.”

Officer Leo Hampton testified on direct examination that two pagers were found during the search and that Poindexter had admitted owning one of them. The court sustained defense counsel’s objection to this testimony, as Poindexter’s statement had not been furnished to defense counsel in discovery. Defense counsel then objected to the court explaining to the jury the basis for the ruling because the explanation suggested to the jury that the statement was reliable evidence excluded for merely technical reasons. The court overruled the objection and explained that the testimony was excluded under rules requiring the prosecution to provide the defense with statements by the defendant prior to trial.

On cross-examination of Officer Hampton, Poindexter’s counsel attempted to explore Hampton’s knowledge of the law requiring officers to knock and announce their business when executing a search warrant. The government objected. Defense counsel explained that he was attempting to challenge the credibility of the officers’ testimony that they knocked at the door and announced their purpose by showing that they had a legal obligation to knock but a practical motive not to do so in order to prevent loss of evidence. The court sustained the objection, holding that it had already been determined at a pretrial hearing that the officers had knocked and that the search warrant was valid.

During closing argument, Day’s counsel recalled that Officer Lonnie Thweatt had testified that it appeared to him that the shaving cream can in which the cocaine had been found had been dusted for fingerprints. Counsel then observed that the government had produced no evidence identifying the fingerprints. The court sustained the prosecution’s objection to the lack of fingerprint testimony argument, stating that “[fingerprint evidence can only be introduced by an expert [who could] explain ... the science, the identification by fingerprints” and that an absence of fingerprint evidence did not “prove anything.”

After the jury convicted both defendants on all counts, Day filed a Fed.R.Crim.P. 29 motion asking the court to set aside the jury verdict against him and grant him either a judgment of acquittal or a new trial. The district court, finding a jury submissible issue whether Day and Poindexter had possessed cocaine with intent to distribute from their home prior to and at the time of the raid, and finding that the presence of the firearms at the home during the drug transactions constituted “using” firearms under the law of the Sixth Circuit, denied the motion.

Following guilty verdicts on all counts, Day was sentenced to consecutive terms of six months’ imprisonment on Count I and sixty months’ imprisonment on Count II. Poindexter was sentenced to concurrent terms of thirty-nine months’ imprisonment on Counts I and III, and a consecutive term of sixty months’ imprisonment on Count II.

II.

A.

Day’s Appeal

1.

Closing Argument

Day argues that this court should reverse his conviction because the district court improperly limited closing argument by preventing Day’s counsel from commenting on a lack of fingerprint evidence and improperly criticized Day’s counsel before the jury. During the cross-examination of Officer Thweatt by Day’s counsel the following exchange occurred:

Q. You received [the shaving cream can] as evidence there on the scene at 766 Los Angeles?

A. Yes, sir. Q. Do you know whether there’s been any effort made to fingerprint that can?

A. It would appear so by the black powder all over it. That looks like the powder that the crime scene people use to raise fingerprints.

During closing argument, Day’s counsel, referring to the foregoing testimony by Officer Thweatt, stated:

Well, the next logical question that I pose to you, ladies and gentlemen of the jury is, whose fingerprints were found on that can?

The government objected and the court sustained the objection, stating:

Let me just explain to the jury about fingerprints. Fingerprint evidence can only be introduced by an expert, and the expert would explain to you the science, the identification by fingerprints. So, it is improper to argue the absence of fingerprints proves anything. This should not be done. You certainly don’t have any evidence to establish that fingerprints proved either of these defendants had anything to do with it, but [Day’s counsel] is out of line when he argues that holds that up and says that you haven’t proved my client guilty because there are no fingerprints. The expert will tell you that that isn’t conclusive.

At a bench conference following the ruling, defense counsel contended that it was indeed proper for him to argue that if the fingerprints had belonged to his client, the prosecution likely would have brought out that information. The court responded:

Don’t you realize that that’s an unfair statement? You know that there could be no fingerprints on there, and it didn’t prove that your client didn’t handle them. I don’t want you to get into that. That’s not fair. That’s below the belt for you defense lawyers to do it. You’re not the only one that does it. That’s not a search for the truth. That’s just trying to fudge on the rules. You ought to be reprimanded for it.

Look, y’all are on notice that this Judge is not going to permit that. I’ve stopped other people from doing it. It’s an attack that, I think, goes to your ethics.

Day contends that these comments were loud enough for the jury to hear. Day objects to both the substance of this ruling and the court’s comments, personally critical of counsel, made in connection with the ruling.

We recognize that the trial court has broad discretion to control closing argument. United States v. Nabors, 761 F. 2d 465 (8th Cir.), cert. denied, 474 U.S. 851, 106 S.Ct. 148, 88 L.Ed.2d 123 (1985). We are also aware that a panel of this circuit previously upheld this district court’s ruling foreclosing comment during closing argument concerning a lack of fingerprint evidence. United States v. Quinn, 901 F. 2d 522 (6th Cir.1990). In Quinn, the court held that on the particular facts of that case, “[t]he district court did not exceed the boundaries of fair comment, particularly since there was no fingerprint testimony or other proof establishing whether such evidence could or could not have been obtained.” Id. at 532 (emphasis added). In the present case, where there was evidence indicating that the can had been dusted for fingerprints, we do not believe the rhetorical question asked by defense counsel during closing argument as to whose fingerprints were on the can was improper. The court was correct that the defendants could not argue that “the absence of fingerprints proves anything,” and that the absence of such evidence “isn’t conclusive.” Defense counsel, however, did not argue that the lack of fingerprint evidence proved anything, or was conclusive. He wished to argue only that the government’s failure to introduce its findings, if any, concerning the presence or absence of fingerprints on a can that had been dusted for fingerprints may raise a reasonable doubt as to whether Poindexter handled the can and, consequently, as to Poindexter’s guilt. We think he might properly have done so.

In every criminal case, the mosaic of evidence that comprises the record before a jury includes both the evidence and the lack of evidence on material matters. Indeed, it is the absence of evidence upon such matters that may provide the reasonable doubt that moves a jury to acquit. The legitimacy of the inference Day’s counsel wished to bring to the jury’s attention-the absence of evidence of Day’s fingerprints on an article containing contraband that had been dusted for fingerprints and which Day was charged with possessing&emdash; did not depend upon the eonclusiveness of the inference. Neither did it depend upon the necessity that it “prove anything,” merely that it had the tendency to do so. Fed.R.Evid. 401. We think the court’s refusal to permit the argument was an abuse of discretion.

Day further argues that the court’s “scathing” criticism of his counsel unfairly prejudiced him in front of the jury. Because Day did not move for a new trial, the record does not establish whether the jury actually heard the court’s comments and thus whether the court’s comments prejudiced Day before the jury. Sidebar conferences with attorneys conducted on the record and out of the jury’s presence are an appropriate component of district court litigation. When, however, such conferences occur in the jury’s presence, this court will assume that the conference is within the jury’s hearing unless the record shows otherwise.

The government’s case against Day was weak. There was no direct evidence that he possessed or sold drugs, and Simmons’ testimony was inconsistent regarding whether she heard the two defendants discussing drugs. We cannot say that the district court’s error in limiting closing argument and sharply chastising Day’s counsel was harmless. We shall, therefore, reverse.

Our disposition of Day’s drug conviction makes it unnecessary to address his argument concerning the sufficiency of the evidence on the firearm charge. That conviction must be reversed also, because it is dependent upon the guilty of the drug trafficking charge.

B.

Poindexter’s Appeal

1.

Limitations on Opening Statement

The district court has discretionary control over opening statements, including the power to exclude irrelevant matters. United States v. Zielie, 734 F. 2d 1447, 1455 (11th Cir.1984), cert. denied sub nom., Gustafson v. United States, 469 U.S. 1189, 105 S.Ct. 957, 83 L.Ed.2d 964 (1985). Poindexter argues that the district court abused its discretion by ruling that counsel could not claim, with respect to the alleged violation of 18 U.S.C. § 924(c), that Poindexter used the gun in self-defense.

As we have said, section 924(c) prescribes a mandatory five year term of imprisonment for anyone who “during and in relation to any crime of violence or drug trafficking crime ... uses or carries a firearm.” It is indisputable that in shooting Officer Vaughn, Poindexter used a gun to protect his home in which he had previously sold and was currently storing drugs.

If the firearm is within the possession or control of a person who commits an underlying crime as defined by the statute, and the circumstances of the case show that the firearm facilitated or had a role in the crime, such as emboldening an actor who had the opportunity or ability to display or discharge the weapon to protect himself or intimidate others, whether or not such display or discharge occurred, then there is a violation of the statute.

United States v. Stewart, 779 F. 2d 538, 540 (9th Cir.1985) (emphasis added), cert. denied, 484 U.S. 867, 108 S.Ct. 192, 98 L.Ed.2d 144 (1987). Because self-defense is irrelevant to a section 924(c) violation, the district court did not abuse its discre tion in preventing Poindexter’s counsel from claiming self-defense.