Daniel Groves was charged in a two-count indictment under the “felon in possession” statute with possessing a firearm and possessing ammunition. See 18 U.S.C. § 922(g)(1). A jury convicted him on both counts. He challenges his conviction on the firearm count on the ground that the evidence was insufficient to demonstrate that the firearm traveled in interstate commerce. On the ammunition count, he faults the district court for denying his motion to suppress evidence obtained in a warrantless search of his apartment. He also complains of evidentiary errors and mistakes in calculating his sentence. This is one of those rare cases in which a defendant succeeds in demonstrating that the evidence was insufficient to prove an element of the crime. We therefore reverse in part, affirm in part and remand to the district court for further proceedings consistent with our opinion.
I.
At approximately 9:40 p.m. on July 5, 2004, South Bend resident Elton Chavez called 911 to report that gunshots were being fired from a building across the street from his residence. Chavez lived in Dismas House, a halfway house for drug addicts and felons. Daniel Groves, the defendant, lived across the street from Dismas House, in an apartment complex. The 911 call was recorded and was рlayed for the jury. Chavez told the 911 operator, “There’s a guy across the street shooting up a shotgun.” He told the operator that the man aimed the gun at Dismas House and that the porch light was on at the building across the street. The operator asked Chavez if he knew who the man was and he replied, “No.” The operator then said, “You don’t know? Do you know if he lives there?” and Chavez replied, “I’m guessing.” Chavez told the operator that he initially thought the blasts were fireworks but that he “bent down and looked underneath the tree and sure enough this guy’s got a shotgun, cocking it, and he wasn’t even aiming it at the sky, he was aiming it over towards our house.” 911 Tr. at l. 1 Although two other people (a female resident of Dismas House and her male visitor) were with Chavez on the porch of Dismas House, only Chavez claimed to have seen the gunman. The male visitor later testified that he could not see the shooter because of the darkness. All three ran into Dismas House after the second shot was fired.
South Bend police officers arrived quickly after the call was made. They first stopped to talk to Chavez who told them that the man with the gun was wearing black and that he fired the shots from the porch across the street where a porch light was on. At trial, he conceded that because *315 it was dark, he could not tell what clothes the shooter was wearing, but that the clothing was black. He also acknowledged at trial that there was a tree blocking his line of vision from the porch of Dismas House to the porch of the building across the street, but maintained he could lean to the left and see the man with the shotgun. The distance between the two porches was approximately 220 feet. After talking to Chavez and the two people who had been with him when the shots were fired, the officers proceeded to the building across the street.
The first officer on the scene, Corporal Taylor, approached Groves, who was standing outside the apartment building wearing a white shirt and dark pants. Taylor asked Groves if he had seen anyone shooting a gun. Groves denied seeing a gun and told Taylor that he had been shooting off fireworks. Taylor asked Groves where his gun was and Groves responded that he never had a gun. In response to Taylor’s questioning, Groves pointed out the porch to his apartment and admitted he was felon. When Taylor then asked Groves if the police could search his apartment, Groves said “No” and told the оfficer to get a warrant. Taylor testified that Groves was “adamant that we could not go in the apartment” and so the officers began to search in the grass for evidence of discharged firearms. Taylor found three 20-gauge shell casings in the grass near the porch. Taylor again approached Groves, told him he had found the shell casings and asked again if he could search the apartment. According to Taylor, Groves “adamantly said no, and he said to go get a search warrant.” The officer then returned to Dismas House, showed Chavez the three shell casings, and said, “Yeah, you’re right. He’s shooting a shotgun.” 2
The officers then applied for a warrant to search Groves’ apartment but a federal magistrate denied the application. On July 21, a few weeks after the incident, police officers returned to Groves’ apartment building. Special Agent Lucas Bat-tani, a South Bend police officer and member of the Project Disarm Task Force, interviewed Darlene Smith, another resident of the building that morning. According to Agent Battani, Smith told the officers that Groves lived in Apartment 3 with Shaunta Foster, and that Foster had lived there for approximately five months. Agent Battani also asked Smith about Groves’ work schedule and determined that he would be at work later that day. Agent Battani returned to the apartment building at 1:30 p.m. with two other members of Project Disarm, including a local officer from the Elkhart Police Department and a federal special agent from the Bureau of Alcohol, Tobacco, Firearms and Explosives (“ATF”). The trio knew from the interview of Smith that Groves would be away at work at that time. Agent Battani had also researched Shaunta Foster in the interim and had determined that a woman by that name was subject to a body attachment warrant. He had not determined whether the Shaunta Foster living with Groves was the same Shaunta Foster associated with the warrant.
*316 The officers went to Groves’ apartment that afternoon to attempt to obtain consent to search from Foster, having been refused by both Groves and a federal magistrate. Both Battani and Foster testified at a suppression hearing; although there were some points of agreement, there were also several important differences in their stories about what happened that day. We begin with Agent Battani’s account. Agent Battani knocked on Groves’ door and when Foster answered, he asked her to step outside to speak with the three officers. Although he was accompanied by two other officers, only Agent Battani spoke to Foster. He asked her if she lived in the apartment and she replied that she did not, that she sometimes stayed at the apartment but did not reside there. Bat-tani asked if there was anyone else in the apartment and Foster replied that her daughter was there. Because Smith told Battani that Foster lived in the apartment, he persisted and asked Foster how long she had lived there, and she replied that she had moved in around February 14th of that year (approximately five months earlier). Foster told Battani that Groves owned the apartment and that he was her boyfriend. In response to questions from Battani, Foster told the agents that she had full access to the apartment and often cleaned it for Groves. When Battani asked for Foster’s consent to search the apartment, Foster balked and told Battani that, without first talking to Groves, she did not believe she had the authority to consent to a search. Battani told her that the consent was not between himself and Groves; it was between himself and Foster. He then showed her a consent form and read it to her line by line, asking her at the еnd of each paragraph if she understood that part of it. Each time, Foster indicated she understood. When he finished reading the form, Battani again asked Foster to consent to a search. This time, Foster agreed to do so and signed the form.
Agent Battani explained that they would be looking for firearms and ammunition and asked Foster to lead them into the apartment. As she walked up the stairs, she told Battani that she had something for him. When they went into the apartment, Foster went into the bedroom and returned with a plastic bag containing marijuana. Foster told the agents that the marijuana was hers and that Groves did not use any type of narcotics. Foster and her daughter sat at the kitchen table with Battani while the other two agents searched the apartment. At times, the searching agents asked Foster questions about the apartment. For example, they asked her which nightstand in the bedroom was hers and whether she had access to both nightstands. As the search proceeded, Foster told Battani that she had never seen firearms in the apartment but that she had seen bullets on Groves’ nightstand. From a drawer in Groves’ nightstand, the officers recovered a magazine containing five .22 caliber bullets that appeared to Foster to be of the same type she had seen earlier. The officers also recovered a few shotgun shells and a bill in Foster’s name for a telephone line at Groves’ apartment. As the officers left the apartment, Battani told Foster that there was a body attachment warrant for her. Later, the officers contacted the local school district and determined that Foster’s daughter was registered at school using Groves’ address as her home address.
Groves was arrested and charged with being a felon in possession of a firearm and being a felon in possession of ammunition. Groves moved to suppress the ammunition discovered in his nightstand, arguing that Foster had neither the actual authority nor the apparent authority to *317 consent to a search of the apartment. The district court held a hearing at which Agent Battani and Shaunta Foster testified. We have already detailed Battani’s testimony above and turn now to the points of divergence in Foster’s testimony. Foster testified that she told Battani that she never lived at Groves’ apartment but merely visited there frequently, sometimes staying overnight. She maintained that she lived at her mother’s apartment. She explained that she gave Grоves the phone line as a gift and that she enrolled her daughter in school using Groves’ address because he lived in a better school district than she did. According to Foster, she repeatedly told Battani that she could not sign the consent form because she did not live there and her name was not on the lease. She asked repeatedly to call Groves and was refused each time. She testified that when she refused to sign the consent, Battani told her that he would take her downtown and take her daughter to Child Protective Services “but that one way or another he was going to get what he needed to go up in there.” Supp. Tr. at 33-34. Foster testified that she signed the consent only because of the threat to remove her child. According to Foster, Battani told her that if she did not consent, she would be criminally charged for any contraband found in the house. Consistent with Battani’s testimony, Foster testified that after she had signed the consent form and the officers were already in the house, Battani informed her there was a warrant out for her arrest. At the suppression hearing, Battani denied ever threatening Foster with the removal of her child.
Following the hearing, the district court issued a short order, concluding that Foster had аpparent authority to consent to the search of Groves’ apartment, that Agent Battani did not engage in inappropriate coercion or threats related to Foster’s daughter, and that Foster consented to the search. Groves took his case to a jury and was convicted on both counts. Because no firearm was ever recovered, his conviction on the firearm possession rested largely on the eye-witness testimony of Chavez, the neighbor who told the 911 operator that he did not know who had fired the shots. In court, Chavez identified Groves with no difficulty. The ammunition seized in the apartment search was entered into evidence over Groves’ objection. The district court sentenced Groves to forty-one months’ imprisonment after adding four levels to his base offense level because he used the weapon in question to commit the offense of criminal recklessness, a class D felony under Indiana law. Groves timely appeals both his conviction and his sentence.
II.
On appeal, Groves contends that the district court erred when it denied his motion to suppress the evidence obtained in the warrantless search of his apartment. He also maintains the district court should have granted his motion for a judgment of acquittal on Count I, the felon in possession of a firearm charge, because the government failed to prove that the firearm in question had traveled in interstate commerce. He complains that the district court erred in allowing the government to rebut some of the testimony of Shaunta Foster when she was the government’s own witness. He contests his sentence on two grounds, claiming first that the district court did not follow the sentencing procedures set forth in Federal Rule of Criminal Procedure 32(i)(4)(A), and second that the court erred in adding four levels to his base offense level.
A.
In reviewing the district court’s denial of a motion to suppress, we review questions
*318
of law
de novo
and factual findings for clear error.
United States v. Denberg, 212
F.3d 987, 991 (7th Cir.2000). “To the Fourth Amendment rule ordinarily prohibiting the warrantless entry of a person’s house as unreasonable
per se,
one ‘jealously and carefully drawn’ exception recognizes the validity of searches with the voluntary consent of an individual possessing authority.”
Georgia v. Randolph,
— U.S. -,
The district court found that Foster’s testimony and the circumstantial evidence presented at the suppression hearing established that “she was involved at the very least in the mutual use of the property in question and had joint access and control.” United States v. Groves, No. 3:04cr0076 (N.D.Ind. Nov. 8, 2004) (hereafter “Suppression Order”), at 1. The court stated that, although Foster exhibited hostility when testifying, “she actually admitted a good deal that relates to her joint or common possession of the apartment in question. The totality of sworn testimony plus the documentary proof causes this Court to conclude that she indeed had joint or common authority with reference to the apartment in question.” Suppression Order at 2. The court noted that consent was the primary issue and made the following findings:
This Court listened carefully and observed keenly both of these witnesses on the witness stand. Agent Lucas Battini [sic] tеstified with caution, great care and restraint. Shaunta Foster testified with great passion and some hostility. After careful consideration and observation, it is the conclusion of this Court that Task Force Agent Lucas Battini [sic] did not engage in inappropriate coercion or threats with regard to Shaunta Foster’s child in order to secure the consent to search the apartment. On this subject, the Court must with some sadness most respectfully decline to credit that portion of Shaunta Foster’s testimony.
Suppression Order at 2. The court then declined to give any weight to the refusal of a judge to grant the officers a search warrant, commenting that the circumstances of that refusal did not bear on the decision the court was required to make. Without further findings, the court ruled, “When it is all said and done, she consented to the search and had apparent authority to do so. The motion to suppress is denied.” Suppression Order at 3. Groves argues on appeal that Foster had neither actual nor apparent authority to consent to the search and that her consent was not voluntary.
A.
We begin with the question of actual and apparent authority. Under
Matlock,
the government bears the burden of demonstrating that the third party possessed common authority over or other
*319
sufficient relationship to the premises or effects sought to be inspected.
Matlock,
Common authority is, of course, not to be implied from the mere property interest a third party has in the property. The authority which justifies the third-party consent does not rest upon the law of property, with its attendant historical and legal refinements, ... but rests rather on mutual use of the property by persons generally having joint access or control for most purposes, so that it is reasonable to recognize that any of the co-inhabitants has the right to permit the inspection in his own right and that the others have assumed the risk that one of their number might permit the common area to be searched.
Matlock,
We cannot discern from the district court’s Suppression Order any findings of fact that support the court’s conclusion that Foster possessed apparent authority. The court states that Foster’s testimony and the documentary evidence establish that she had mutual use and joint access and control of Groves’ apartment. The court also states that Foster “admitted a good deal that relates to her joint or common possession of the apartment.” But these are legal conclusions rather than factual findings. We do not know on what facts the court relied in reaching this conclusion, nor do we know what part of the testimony the court credited and what part *320 the court disbelieved. There were significant differences between the stories told by Agent Battani and Shaunta Foster at the suppression hearing. The only testimony from Foster that the court declined to credit was her claim that Agent Battani threatened to remove her child if she refused to consent to the search. But this fact related to the voluntariness of her consent and not to her actual or apparent authority to consent. Moreover, these legal conclusions are consistent with a finding of actual authority but the court ultimately found that Foster had apparent authority to consent to the search. Without knowing which testimony and which documents were credited, without knowing on what facts the court relied in reaching its conclusion, and without knowing whether the court concluded that Foster’s authority was actual or apparent, we cannot review the court’s сonclusion that Foster had authority to consent to the search. We will therefore remand for the district court to make fact-findings in support of its conclusion and to clarify whether Foster had actual or apparent authority to consent, or indeed whether she had any authority to consent to a search of the apartment and the nightstand.
After we heard oral argument in this appeal, the Supreme Court held in
Randolph
that “a warrantless search of a shared dwelling for evidence over the express refusal of consent by a physically present resident cannot be justified as reasonable as to him on the basis of consent given to the police by another resident.”
The tenants might have made an exceptional agreement that no one would admit a guest without the consent of all, but the police were entitled to rely on the more usual expectation that no such agreement existed.
Randolph,
*321
The Court considered the continued significance of
Matlock
in light of its holding in
Randolph
and drew what it called “a fine line[.]”
[I]f a potential defendant with self-interest in objecting is in fact at the door and objects, the co-tenant’s permission does not suffice for a reasonable search, whereas the potential objector, nearby but not invited to take part in the threshold colloquy, loses out.
This is the line we draw, and we think the formalism is justified. So long as there is no evidence that the police have removed the potentially objecting tenant from the entrance for the sake of avoiding a possible objection, there is practical value in the simple clarity of complementary rules, one recognizing the co-tenant’s permission when there is no fellow occupant on hand, the other according dispositive weight to the fellow occupant’s contrary indication when he expresses it.
Randolph,
B.
We turn to the issue of voluntariness. Groves argues that Foster’s consent was not given voluntarily. He contends that the district court did not resolve illogical and inconsistent statements in Agent Battani’s testimony and that the district court failed to make findings of fact relevant to the resolution of the voluntariness question. The government must demonstratе by a preponderance of the evidence that consent to search was in fact voluntarily given, and not the result of duress or coercion, express or implied.
Bustamonte,
Therein lies our problem, for the district court made only one finding relevant to the issue of voluntariness and that finding is somewhat ambiguous. The district court noted only that it credited Battani’s testimony over that of Foster on the issue of whether Battani engaged in “inappropriate coercion or threats with regard to Shaunta Foster’s child in order to secure the consent to search the apartment.” Suppression Order at 2. The use of the word “inappropriate” in qualifying “coercion and threats” suggests that the district court may have found some level of threats or coercion appropriate. Any level of threats or coercion related to Foster’s child would weigh against a finding of voluntariness. Moreover, we know nothing about Shaunta Foster’s level of education, her intelligence, or her age. The transcript gives us pause on the issues of education and intelligence; Foster referred to the ATF agent as “FTD,” for example, and some of her speech is consistent with a lack of educatiоn.
4
In weighing the totality of the circumstances surrounding the consent to search, the district court should have considered those factors together with the number of officers present, what show of force they made, whether they were armed and whether their weapons were visible. The court did not address Foster’s claim that Battani threatened to charge Foster with any contraband found in the apartment or her claim that Battani would hold her downtown while he obtained the paperwork he needed to enter the apartment, implying that he could get a warrant when he had tried and already failed to do so.
See United States v. White,
C.
Groves raises two challenges to his conviction for possession of a firearm by a felon. First, he argues that there was insufficient evidence of an independent basis, source or origin for the in-eourt identification of Groves by Chavez. Second, he maintains that there was insufficient evidence that the shotgun in question was transported in, possessed in, or affected interstate commerce. We need not address the in-court identification because Groves prevails on his clаim that the government failed to present sufficient evidence on the interstate commerce element of section 922(g)(1).
Section 922(g)(1) provides that it “shall be unlawful for any person ... who has been convicted in any court of, [sic] a crime punishable by imprisonment for a term exceeding one year ... to ship or transport in interstate or foreign commerce, or possess in or affecting commerce, any firearm or ammunition; or to receive any firearm or ammunition which has been shipped or transported in interstate or foreign commerce.” 18 U.S.C. § 922(g)(1). The shotgun that Groves was alleged to have fired on July 5, 2004, was never recovered. Chavez, the only witness to testify to the existence of the shotgun, did not identify a make, model, or manufacturer and provided no description of the firearm except to say that he heard a sound like a shotgun being loaded and then saw a shotgun in the hands of the shooter. He told the 911 operator that it “looked like a sawed off shot gun.” 911 Tr. at 1. In seeking to prove the interstate commerce element of the crime, the government produced testimony from John Phinney, a criminal investigator with the ATF. The prosecutor asked Phinney, “[A]re there any major manufacturers of shotguns in the state of Indiana?” Phin-ney replied, “No, sir, there are not.” The prosecutor asked, “So if a shotgun was found in Indiana or was present in Indiana, it would not have been manufactured by any major manufacturer; is that correct?” Phinney replied, “That is correct.” Trial Tr., Vol I, at 97. For the ammunition recovered from Groves’ apartment on July 21, 2004, Phinney was able to identify the manufacturers and testified that the shells and bullets were manufactured outside of Indiana and therefore had traveled in interstate commerce. Trial Tr., Vol. I, at 98-99. Groves does not challenge the sufficiency of the interstate commerce evidence for the ammunition charge.
In reviewing a defendant’s challenge to the sufficiency of the evidence, we view the evidence in the light most favorable to the prosecution.
United States v. Bernitt,
The government’s main proof of the interstate commerce element for the firearm charge was Phinney’s testimony that there were no “major manufacturers” of shotguns in Indiana. But the agent gave no definition of “major” and was never asked about minor manufacturers or statistical probabilities that the gun was manufactured outside of Indiana. Without some indication of the meaning of this testimony, without placing it in the context of the gun manufacturing industry, it is simply too vague to support proof of this element of the crime beyond a reasonable doubt. Minor manufacturers could, collectively, manufacture the majority of shotguns produced. Any conclusion drawn from this testimony would be the result of pure speculation as to what the agent meant by “major.” Speculation cannot be the basis for proof in the civil context much less the basis for proof beyond a reasonable doubt.
Wainscott v. Henry,
The government protests that if we hold this proof insufficient, the government will never be able to prove the interstate commerce element in a case where the defendant successfully disposes of a firearm before trial, in contravention of our cases that specifically hold that it is not necessary for the government to produce the firearm at trial. This is simply not true. Granted, the government’s case was hampered by the absence of the gun. In some cases, the government will be able to prove that a firearm wаs manufactured in another state because a witness is able to identify the make, model or manufacturer of the gun. No witness in this case was able to do so. But the government could have questioned the ATF agent further to determine what he meant by “major.” As we pointed out at oral argument, follow-up questions could have clarified (if this is indeed the case) that there are no companies manufacturing shotguns in Indiana but that individuals or small enterprises sometimes manufacture this type of firearm. Further questioning could have quantified the percentage of shotguns that *325 are manufactured by major manufacturers versus by individuals or by other minor manufacturers. If the percentages demonstrate that it is highly unlikely that the shotgun was manufactured in Indiana, such testimony could support proof of this element. At oral argument, the government stated that the ATF expert was unwilling to testify any more specifically about shotgun manufacturers in Indiana. Perhaps the facts did not bear out the government’s view of “major” versus “minor.” We cannot say on this record why the expert declined to offer any more detail. But there is insufficient evidence to prove that the shotgun moved in interstate commerce at any point in time.
The government next argues that, even if the shotgun was manufactured in Indiana, thе prosecution could (and did) prove this element of the crime by demonstrating that Groves’ possession of the shotgun
affected
interstate commerce. The government maintains that, so long as the shotgun possession had some minimal nexus to interstate commerce, we may apply the aggregation doctrine first described in
Wickard v. Filburn,
The government suggests that it provided sufficient proof of the minimal nexus described in Wickard in several ways. First, the government argues that it was Groves who fired the shotgun towards Dis-mas House where Chavez, a construction worker who ran his own business, resided. According to the government, this conduct rendered Dismas House at least temporarily unsafe and ineffective as a residence for convicts, drug addicts, employers and workers. Displacement of workers could result in jobs moving out of state which, in turn, would affect the cost of labor and the local demand for out-of-state labor. Moreover, the government would have to pay for other accommodations for the residents of Dismas House or would have to release them, imposing a financial burden or rendering the area unsafe, which could cause citizens to leave the state of Indiana. Second, the government explains, Groves possessed shotgun shells that were manufactured out of state. A jury could reasonably conclude that the missing shotgun was capable of firing these shells, and thus the shotgun would be a “market compliment” [sic] for the shells, affecting the demand for оut-of-state shells. Third, and in a similar vein, the government argues that a purely intrastate firearm is a market substitute for a gun obtained through interstate commerce. As such, a failure to regulate the possession of intrastate fire *326 arms along with interstate firearms would undercut the regulation of the interstate market. Given where this line of argument is headed, we are half-surprised that the government failed to argue that Groves’ use of the firearm as a market substitute for fireworks on that July 5th evening undercut the interstate market in firecrackers.
These might be viable arguments if the Supreme Court had not completely rejected them eleven years ago in
United States v. Lopez,
The Supreme Court noted that there are three broad categories of activity that Congress may regulate under its commerce power. “First, Congress may regulate the use of the channels of interstate commerce.”
Lopez,
Subsection 922(q), unlike section 922(g), had no express jurisdictional element that would limit its reach to firearm possessions that additionally had an explicit connection with or effect on interstate commerce. In
Lopez,
the government
*327
nevertheless sought to defend the statute on the grounds that possession of a firearm in a local school zone does in fact substantially affect interstate commerce. In particular, the government argued that possession of a firearm near a school could result in violent crime; violent crime would, in turn, affect the national economy in several ways. First, thе costs of violent crimes are substantial, and through the mechanism of insurance, the costs are spread throughout the population. Second, violent crime reduces the willingness of individuals to travel to parts of the country that are deemed unsafe. Third, the presence of guns near schools poses a threat to the educational process by threatening the learning environment, ultimately resulting in a less educated and less productive citizenry, which in turn would have an adverse effect on the nation’s economic well-being. Lopez,
The Court reasoned that if it accepted the government’s argument about the costs of violent crime and the effects on the national economy, there would be no limit to the activities that Congress could regulate, even in areas where States traditionally have been sovereign such as education and law enforcement. Lopez,
We arе faced here with a statute that, unlike Subsection 922(q), includes a requirement that the gun possession be “in or affecting commerce.” As we found above, the government failed to produce sufficient evidence that the gun had traveled in interstate commerce, and the government is thus left to argue the same sorts of tenuous connections to commerce that the Court expressly rejected in Lopez. For example, the government contends that Groves’ possession of the firearm led to the violent act of firing the gun toward a halfway house where convicts and drug addicts lived. In turn, this violence could displace workers, encourage people to move from the unsafe area, and increase the government’s cost of housing persons who would otherwise be able to live in Dismas House. In Lopez, the Supreme Court rejected the costs of violent crime as the basis for upholding a statute criminalizing gun possession; the Court rejected this rationale because it would federalize areas of criminal law that have historically been the province of the States. A rationale that could not sustain Subsection 922(q) cannot be the basis for upholding a conviction under section 922(g). 6 Failing to require the government to prove an essential element of the crime affects substantial rights and seriously affects the public reputation of judicial proceedings. Because allowing a conviction to stand without proof of an essential element of the crime meets the standard for plain *328 error, we reverse the firearm possession conviction. As we noted above, we need not address Groves’ alternate argument regarding the sufficiency of the in-court eyewitness identification because we reverse Count I on Commerce Clause grounds.
D.
Groves contends that the district court erred when it allowed the government to present rebuttal evidence in response to the testimony of Shaunta Foster. According to Groves, the only witness called in the defense case was Michael Bennett, an investigator for the Federal Defender’s office, who testified about measurements of the distance between the porch of Dismas House and the porch of Groves’ apartment. Bennett also presented pictures he had taken of the scene. The government’s rebuttal witnesses were the six officers who were on the scene on July 5th. Each countered statements by Shaunta Foster, whо testified that the officers surrounded Groves that night in a threatening fashion, clutching batons, and that she had seen the officer who collected shotgun shells that night on the other side of the fence in a neighbor’s yard, rather than near the porch of Groves’ apartment. The government also recalled Agent Battani to counter other statements Foster made at trial.
We review the district court’s decision to allow rebuttal testimony for abuse of discretion.
United States v. Grintjes,
The court was within its discretion to allow the rebuttal testimony of the six officers present on July 5th in order to counter Foster’s testimony under defense questioning. Because the court allowed defense counsel to question Foster out of order rather than call her back to the stand later, this part of her testimony was part of the defendant’s case-in-chief. As such, the government was an adverse party to that testimony and could rightly challenge it. Allowing Agent Battani’s rebuttal testimony is a closer question. When Foster testified that Battani threatened her, she did so in response to the government’s questioning in its casein-chief. She was not, at that time, an adverse witness to the government, and a party is not generally entitled to rebut its own witness. As the court admonished the government, ‘You put her on. You knew what she was going to say. You led her right into it. Now, you’re a very good lawyer and you’ve got to live with the consequences of what you do.” Tr. Vol. I, at 82. To the extent it was an error for the district court nonetheless to allow rebuttal by Battani, we *329 think the error was harmless. Foster’s statement that Battani threatened her was largely irrelevant to the issues the jury had to decide. It is unlikely that Battani’s brief rebuttal affected the jury’s assessment of the relative credibility of Foster and Battani on any issue in the trial.
E.
Finally, Groves challenges the court’s Guidelines calculation and the manner in which the court held the sentencing hearing. Because we have reversed the conviction on Count I, the district court must re-sentence Groves. We will address his arguments to the extent that they are relevant to re-sentencing. First, he contends that the district court failed to follow the sentencing procedure established by Federal Rule of Criminal Procedure 32(i)(4), “Opportunity to Speak.” Under that provision, before imposing sentence, the court must:
(i) provide the defendant’s attorney an opportunity to speak on the defendant’s behalf;
(ii) address the defendant personally in order to permit the defendant to speak or present any information to mitigate the sentence; and
(iii) provide an attorney for the government an opportunity to speak equivalent to that of the defendant’s attorney.
According to Groves, the court pronounced sentence prior to allowing Groves, his attorney, or the government attorney to speak. The government posits that the court merely announced preliminary findings, then heard all the parties, and subsequently imposed the sentence, all in compliance with Rule 32.
We review the question of whether the district court complied with mandatory sentencing procedures under a non-deferential standard of review.
See United States v. Rodriguez-Alvarez,
The government characterizes the court’s initial remarks as “tentative sentencing decisions” and argues that all parties were invited to speak before sentence was “formally imposed.” The court’s language, though, was not particularly tentative. The tone of the court during the parties’ remarks suggests that the court had already ruled on every issue raised and was unwilling to reconsider any of those rulings based on the parties’ arguments and statements. Although the sentence may not have been “formally imposed” before the parties spoke, this colloquy was not entirely consistent with the spirit of Rule 32(i)(4)(A). The judge essentially signaled to the parties that his ruling was final before the hearing began. But the court did comply with the letter of Rule 32; it did not formally enter the sentencing order until after the parties had an opportunity to speak. On remand, we have no doubt that the court will fully comply with Rule 32(i)(4)(A) by considering the parties’ arguments and statements before the sentence is imposed.
Groves also challenges the court’s calculations under the Guidelines, complaining that the court exceeded its authority in adding four levels to Groves’ offense level based on a finding that Groves used the shotgun to commit the offense of criminal recklessness under Indiana law.
See
U.S.S.G. § 2K2.1(b)(5). Section 2K2.1(b)(5) provides for a four-level increase to the base offense level if “the defendant used or possessed any firearm or ammunition in conneсtion with another felony offense.” Application Note 4 of the Commentary for that provision defines “felony offense” as “any offense (federal, state, or local) punishable by imprisonment for a term exceeding one year, whether or not a criminal charge was brought, or conviction obtained.” In the PSR, in reporting the government’s version of the offense, the probation officer noted that Groves possessed and used the shotgun (and presumably ammunition, given the shells found on the ground near the porch that night) to fire shots in the direction of Dismas House, endangering the lives of the three people present on the porch. PSR, ¶ 6(j). Groves did not object to this paragraph, and did not object at the sentencing hearing to the additional four levels under section 2K2.1(b)(5). The argument is therefore waived and we review the court’s calculation for plain error.
Allen,
The Indiana statute provides that a person who recklessly, knowingly, or intentionally performs an act that creates a substantial risk of bodily injury to another person commits criminal recklessness. Ind.Code § 35-42-2-2. If the offense is committed while armed with a deadly weapon, it constitutes a Class D felony under Indiana law.
Id.
The court found that Groves committed this offense by firing the shotgun toward Dismis House.
7
The testimony of Chavez and the testimony of the officers who retrieved spent shotgun shells from Grove’s yard that night together were sufficient to demonstrate by a preponderance of the evidence that Groves committed this offense. We see no error in the district court’s calculations. Groves complains that the jury did not find beyond a reasonable doubt that he eommit-
*331
ted this Indiana offense and he did not admit the facts necessary to prove that charge beyond a reasonable doubt. He contended that the court’s findings were made under, at most, a preponderance of the evidence standard. He characterizes the use of the preponderance standard as a violation of
United States v. Booker,
III.
On remand, the district court should enter fact-findings in support of its ruling on the motion to suppress, and should consider the totality of the circumstances in determining whether Foster’s consent was voluntarily given. If Foster’s consent was not vоluntary, the suppression ruling cannot stand, and the conviction on the ammunition count would be in jeopardy. We do not mean to suggest a particular outcome for the motion to suppress; we note only that, as it stands, there is insufficient fact-finding and insufficient analysis for appellate review. It is possible that after the court makes the appropriate findings in support of its decision to deny that motion, defense counsel may withdraw its objection to the ruling; it is also possible there may still be some non-frivolous basis for further review. We reverse the conviction on Count I, the firearm possession charge, for the reasons stated above. In light of that reversal, the district court should resentence Groves. At any new sentencing hearing, the district court should allow an appropriate Rule 32 colloquy before imposing sentence. In all other respects, we affirm.
Notes
. Neither the tape nor the transcript of the 911 call appear in the certified record on appeal. Groves included a copy of the transcript in the appendix filed with his opening brief, embedded between pages 23 and 24 of Volume I of the trial transcript. We will refer to this transcript as the "911 Tr.”
. There were a few minor disсrepancies between the officer’s testimony at trial and the report he filed immediately after this incident. For example, in the report, Taylor stated that when he first approached the house across the street from Dismas House, he found Groves shooting off fireworks; at trial he stated that Groves was standing outside the apartment building and told him he had been shooting off fireworks. None of these discrepancies are material to the issues on appeal and so we need not consider them further.
. This is certainly not an exhaustive list and we do not mean to suggest that district courts should use this as a checklist of factors in determining actual or apparent authority. Rather, it is offered to show the types of facts that should and could be considered in evaluating the issue of authority to consent to a search.
. “ATF” refers to the Bureau of Alcohol, Tobacco, Firearms and Explosives. We presume that “FTD” refers to "Florists' Telegraph Delivery,” a well-known flower delivery service. It is certainly possible that Foster simply misspoke, and we do not mean to disparage her in any way. But the issue of intelligence and education was one for the government to prove, and in viewing the record, in thе absence of any findings by the district court on this issue, this malapropism along with numerous grammatical errors in Foster’s testimony prompt us to seek express findings from the district court.
. Following Lopez, Congress enacted a new version of Subsection 922(q) that contains a requirement that the firearm "has moved in or that it otherwise affects interstate or foreign commerce.”
. We likewise reject the government's argument that the case should be controlled by
Gonzales v. Raich,
. The possibly intrastate nature of the shotgun does not matter in this context. The origin of the gun is irrelevant under Indiana state law. Moreover, the use of the gun at this stage of the sentencing proceedings would be evaluated under the standards for relevant conduct, where the preponderance standard applies.
