This appeal brings before us the convictions of Gurmail Singh and Harjit Dhesi, who were convicted for harboring aliens for commercial gain, in violation of 8 U.S.C. § 1324. Singh was indicted, but acquitted, of a felon in possession of a gun charge in violation of 18 U.S.C. § 922(g)(1). On appeal, Singh challenges the district court’s failure to sever that count in the indictment from this trial. Singh argues that the count was unrelated to the harboring charge, and, because inclusion of the count allowed the government to introduce inflammatory evidence against him, including a felony conviction and possession of various weapons, he was unfairly and irreparably prejudiced by the district court’s abuse of discretion in failing to sever that count from this trial. Both defendants appeal a series of eviden-tiary rulings, the jury instructions and the failure to compel the production of documents. Because we hold that the only reversible error is the district court’s failure to sever the felon in possession charge, we affirm Dhesi’s conviction and sentence, but reverse Singh’s conviction and sentence and remand for further proceedings.
I
Appellants Singh and Dhesi operated convenience stores in north Texas. In early 1999, they hired three aliens from India to work at their convenience stores. The aliens were all employees or former employees of International Forestry Services, an organization that had arranged for the individuals to come to the United States on work visas.
On August 20, 1999, federal agents executed an INS administrative arrest warrant on Singh at his residence. Singh consented to a search of his bedroom. This search produced a photograph of Singh, a convicted felon, holding an assault style weapon in front of a 1996 calendar. 1 One of the officers recognized the background of the photograph as the back room of one of Singh’s convenience stores.
Later that afternoon, the officers entered the convenience store and sought consent to search from the clerk in charge. Although they obtained written consent to search, the district court held that this search was illegal because the language barrier prevented the consent from being knowingly and voluntarily given. During the search of the back room, the officers found two individuals who stated that they, as well as the clerk in the front of the store and another individual, were illegal aliens from India who lived in the back room and worked in the defendants’ convenience stores. The officers also found a handgun (the subject of Count Four of the indictment) and the passports of three of the four Indian nationals who lived in the back room.
A few days later, the officers returned to the convenience store in an attempt to find the Indian nationals. Although they had disappeared from the area, 2 later, a man who had purchased one of the convenience stores from the defendants cooperated with the officers in an attempt to locate them. Eventually, the aliens agreed to cooperate with the United States in the prosecution of Singh and Dhesi. *533 On January 12, 2000, a grand jury indictment charged Dhesi and Singh with three counts of harboring illegal aliens for commercial advantage, in violation of 8 U.S.C. §§ 1324(a)(l)(A)(iii), 1324(a)(l)(A)(v)(II) and 1324(a)(1)(B)©. A fourth count charged Singh with being a felon in possession of a firearm, in violation of 18 U.S.C. § 922(g)(1). The judge granted a motion to suppress evidence— that is, the passports and the handgun— arising out of the search of the convenience store because the language barriers prevented effective consent. The jury found both defendants guilty on the three counts of harboring illegal aliens. Singh, however, was acquitted on the count of possession of a firearm. Dhesi was sentenced to four months of house arrest and three years’ probation and was directed to pay a $9,000 fine. Singh was sentenced to ten months in prison.
II
On appeal, Singh argues that his convictions should be reversed because the district court abused its discretion by failing to sever Count Four—the felon in possession of a firearm charge—because this count was unrelated to the harboring counts and it allowed the government to introduce highly prejudicial evidence that resulted in an unfair trial on the remaining counts. That evidence included Singh’s purported earlier involvement in a firearms deal, photographs depicting Singh holding an assault rifle, testimony that Singh perpetually carried a firearm, and evidence that Singh had previously been convicted of a felony—unlawful possession of food stamps.
We review a district court’s denial of a motion for severance for abuse of discretion.
United States v.
Bullock,
The preliminary inquiry in reviewing the denial of a motion to sever is whether initial joinder was proper under Federal Rule of Criminal Procedure 8(a).
United States v. Holloway,
The government contends that the weapons charge is connected to the harboring charges because Singh threatened the aliens with violence to maintain control over them, and therefore is part of a common scheme or plan. The alleged link between the weapons charge and the harboring charge, however, is tenuous at best. There was no significant evidence that Singh used the gun described in the indictment to intimidate the aliens. In fact, the government produced evidence only that Dhesi, not Singh, had threatened one of the aliens with a weapon. Although the aliens testified that they were aware that Singh had a handgun under the counter of the store, and in the ceiling of the bathroom of the apartment in the back of the convenience store, there was no evidence that Singh threatened the aliens with the gun or intended to use it against them. Because there was no evidence that Singh’s alleged possession of the gun had any connection to his housing and hiring of illegal aliens, the gun count was unrelated to the harboring count. Thus, initial join-der was not appropriate.
Even though the counts were improperly joined, reversal is only appropri
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ate if there is clear evidence of prejudice resulting in an unfair trial.
Bullock,
Here, before the trial even began, the jury was told that Singh was a convicted felon when the jury was read the indictment. Although the district court did not allow the government to offer evidence of Singh’s prior conviction until the court found that the government had sustained its burden of proof on the other elements of Count Four, the government, in the course of trying to prove the gun count, was permitted to introduce photographs of Singh with assault type weapons and testimony that Singh had been involved in a firearms transaction with other Sikhs. These events had occurred in 1994. Although eleven firearms were confiscated from Singh, they were all found to be legal and eventually returned to Singh. It is true that the district court included a jury instruction that the previous conviction could not be used for any purpose other than deciding the felony element of Count Four. 3 But the element of the harboring offense that was most seriously contested by Singh was his alleged knowledge that the Indians were working illegally, knowledge that he denied. Thus, with Singh’s credibility in the balance on a critical element of the offense, evidence that Singh formerly had been convicted of a felony, had engaged in a transaction involving firearms, and perpetually carried a firearm was arguably determinative as to whether the jury would believe him on this crucial issue of fact. Furthermore, the evidence on the gun charge was weak (the weapon listed in the indictment was suppressed because it was found during the search of the convenience store) and the jury ultimately found Singh not guilty on Count Four. We therefore conclude that the inclusion of the weakly supported firearm charge, and the evidence that was admitted based on its relevance to this count, seriously and improperly prejudiced Singh. In short, it resulted in an unfair trial. Thus, because initial joinder was inappropriate and the failure to sever was prejudicial, we hold that the district court’s denial of Singh’s motion for severance constitutes an abuse of discretion, which, under the circumstances here, requires that we reverse Singh’s conviction.
Ill
Although the district court abused its discretion in failing to sever Count Four, the evidence that was introduced as a result of this charge prejudiced only Singh, *535 not Dhesi. We cannot, therefore, reverse Dhesi’s conviction on this basis. We will consider, then, the other issues raised on appeal that are said to affect Dhesi’s conviction.
Dhesi contends that the district court erred in failing to suppress the testimony of the three illegal aliens. He argues that their identity would not have been discovered but for the illegal search of the convenience store. Although the district court suppressed other evidence from the search, it held that suppression was unnecessary because the witnesses’ testimony was too attenuated from the illegal search and because the witnesses inevitably would have been discovered.
As a general matter, the exclusionary rule prohibits the introduction at trial of all evidence that is derivative of an illegal search, or evidence known as the “fruit of the poisonous tree.”
United States v. Grosenheider,
The Supreme Court has distinguished between inanimate evidence produced by an illegal search and witness testimony whose source is found in the Fourth Amendment transgression.
United States v. Ceccolini,
Here, the government had obtained an arrest warrant for Singh, and the store was under surveillance. Government agents had noted the other individuals entering the store premises from the rear. One of the illegal aliens was waiting on customers in the front of the store, which was open to the public. The aliens voluntarily agreed to be interrogated after the illegal search, and the store clerk was a cooperating witness. These facts add up to a reasonable probability that, during the course of the investigation, the government inevitably would have lawfully discovered that the aliens lived in the convenience store, evén if the illegal search had never occurred. The district court therefore did not err in refusing to suppress the testimonial evidence of the witnesses.
Finally, Dhesi challenges a variety of other trial and • discovery determinations by the district court. We find no merit in any of these contentions. 4 We therefore affirm Dhesi’s conviction and sentence.
*536 IV
In conclusion, we REVERSE Singh’s conviction and sentence on all counts and REMAND for further proceedings not inconsistent with this opinion because we hold that the district court abused its discretion in denying Singh’s motion to sever Count Four. Because we find no other reversible error, however, Dhesi’s conviction and sentence are AFFIRMED,
AFFIRMED in part; REVERSED and REMANDED in part.
Notes
. On February 9, 1996, Singh pled guilty to the federal felony of unlawful possession of food stamps and was sentenced to serve three years’ probation. It is unclear exactly when the photograph was taken.
. At trial, the aliens testified that Singh and Dhesi kicked them out of the apartment without their belongings and told them to flee the area.
. Although we have noted that possible prejudice resulting from the failure to sever charges may be cured with proper instructions,
see Bullock,
. Specifically, Dhesi argues that the district court abused its discretion by: (1) excluding testimony relating to the aliens’ payment for visas to the United States, (2) excluding expert testimony on whether the defendants would have been aware of the aliens' immigration status if they had complied with federal employment regulations, (3) failing to compel the production of documents, and (4) incorrectly addressing the jury on the required mental state and on federal regula
*536
tions relating to the hiring of aliens. Because none of these rulings constituted "clear ... abuse that resulted in the deprivation of some substantial right of a party,”
United States v. Okoronkwo,
