SWYGERT, Senior Circuit Judge.
Defendants Clifford Howard (“Clifford”) 1 and Charles Wayne Shelton (“Charles”) appeal from their convictions in the United States District Court for the District of Kentucky for conspiracy and mail and wire fraud. The indictment alleged that defendants conspired with Harriet Shelton Howard (“Harriet”) (wife of defendant Clifford and sister of defendant Charles) and Johnny Howard (“Johnny”) (unrelated to the other Howards) to defraud Grange Mutual Casualty Company by burning the residence of Clifford and Harriet. The indictment alleged that the residence was burned by Charles with the assistance of Johnny. The indictment further charges that the scheme continued after the fire with substantive acts of mail and wire fraud in an attempt to perfect the claim for insurance proceeds on the fire loss.
The case was referred by .the district court to a magistrate for consideration of various pretrial matters. After a hearing, the magistrate found that the tape recording of conversations between Charles and Johnny did not implicate Charles’ sixth amendment rights and that the tapes met the authenticity and accuracy requirements set forth in United States v. Starks, 515 F.2d 112, 121 n. 11 (3rd Cir.1975). The magistrate recommended that the defendants’ motion to suppress the tapes be denied, Magistrate’s Report and Recommendation filed October 15, 1982, and the district court adopted this recommendation, Order filed December 23, 1982.
The case was tried to a jury. After ten hours of deliberation, the jury found defendants guilty on all counts. Defendants thereafter filed a motion for a new trial on the ground that one juror deliberately concealed material information on voir dire. Defendants also moved for a new trial on the ground that two other jurors were exposed to extraneous prejudicial information. The motion was referred to the magistrate who recommended that a new trial be granted on the basis that a juror deliberately concealed information on voir dire. The magistrate recommended that the motion for a new trial be denied in all other respects. Magistrate’s Report and Recommendation filed May 20, 1983. After additional testimony in the district court, the court concluded that a new trial was not warranted on any grounds. Opinion and [223]*223Order filed June 9, 1983; Findings of Fact, Conclusions of Law, and Order filed July-20, 1983. The defendants were sentenced to ten years each with five years probation following their release from prison.
Defendants argue on appeal that: (1) the district court erred in denying their motion for a new trial on the ground that a juror deliberately concealed information on voir dire; (2) the district court abused its discretion by denying their motion for a new trial on the ground that another juror was shown to lack impartiality; (3) the court erred in permitting the United States to introduce tape recordings of conversations between Charles and Johnny which were held in violation of Charles’ sixth amendment right to counsel; (4) the court erred in admitting evidence illegally seized from the Howards’ residence; and (5) the court erred in admitting out-of-court statements of Charles and Johnny against defendant Clifford.
I
Sandra Rae Huffman was impaneled as an alternate juror but replaced a regular juror who was dismissed for illness. During voir dire, defense counsel asked whether any of the prospective jurors had “any relatives or close personal friends ... who happen ... to be a law enforcement officer?” ’Excerpted Transcript of Voir Dire on February 28, 1983 at 66. At least six persons responded affirmatively and were subjected to additional questioning. Id. at 66-70. Huffman did not respond. At the posttrial hearing, Huffman admitted that her brother-in-law was an officer with the Portsmouth, Ohio Police Department at the time of the trial and that she considered him a relative. When asked why she did not respond to the question, Huffman stated:
Well, they were asking, in other words, if it would have any effect if I was chosen to sit on the jury, would it make a difference in what I decided. It wouldn’t have any effect whatsoever, and he was in the State of Ohio, and I just — this was my first time being called to jury service, and I just didn’t realize that it would be important, you know, that I didn’t mention his name.
Transcript of Magistrate’s Hearing on April 29, 1983 at 80. Huffman gave similar responses each time she was asked why she failed to respond to the question on voir dire. See id. at 82, 88.
Defendants argue that bias on the part of Huffman must be presumed as a matter of law under the rule set forth in McCoy v. Goldston, 652 F.2d 654 (6th Cir.1981). In McCoy, this court stressed the importance of peremptory challenges, id. at 657-58, and found that the right to the exercise of such challenges is prejudicially impaired by a prospective juror’s deliberate concealment of information on voir dire, id. at 658. The court concluded that bias must be presumed and a new trial granted “when a juror deliberately concealed information or gave a purposefully incorrect answer.” Id. at 659. McCoy set forth three factors to be considered in determining whether a juror has deliberately concealed information or purposefully given an incorrect answer;
A. Whether the question asked sufficiently inquired into the subject matter to be disclosed by the juror.
B. Whether the response of other jurors to the question asked would put a reasonable person on notice that an answer was required.
C. Whether at any time during the trial the juror became aware of his false or misleading answer and failed to notify the district court.
Id. at 658-59 (footnotes omitted).
The government argues that McCoy has been limited if not overruled by Supreme Court decisions in Smith v. Phillips, 455 U.S. 209, 102 S.Ct. 940, 71 L.Ed.2d 78 (1982), and McDonough Power Equipment, Inc. v. Greenwood, 464 U.S. 548, 104 S.Ct. 845, 78 L.Ed.2d 663 (1984). Cf. United States v. Pennell, 737 F.2d 521 at 533 n. 11 (6th Cir.1984) (after Phillips, a “hearing at which the defendant bears the burden of proving actual bias ... is adequate in most eases involving ... juror [224]*224misconduct”). In Smith, supra, the Court held that the due process clause does not require the district court in a habeas proceeding to presume bias on the part of a juror in a state criminal proceeding who had an application for employment pending in the state prosecutor’s office. 455 U.S. at 214-18, 102 S.Ct. at 944-46. In McDonough, a plurality of the Court held that a new trial is warranted only where a party demonstrates “first ... that a juror failed to answer honestly a material question on voir dire, and then further ... that a correct response would have provided a valid basis for a challenge for cause.” 104 S.Ct. at 850. Two Justices concurred in the judgment only and three Justices joined a concurring opinion which stated that bias may be presumed in some cases. Id. (Blackmun, J., with whom Stevens, O’Con-nor, JJ., join, concurring); id. (Brennan, J., with whom Marshall, J., joins, concurring in judgment).
We need not decide whether these cases overrule McCoy v. Goldston, supra, because we find that even under McCoy, implied bias is not warranted in the instant case. Defendants have failed to prove that Huffman deliberately concealed information. McCoy involved a voir dire question almost identical to that involved in the instant case. The juror in McCoy gave no response to the question although her son was training to become a probation officer. The court found this evidence sufficient to establish a prima facie case of deliberate concealment by the juror and to require a posttrial hearing at which the juror could be examined. 652 F.2d at 659. The court did not find the evidence necessarily sufficient to require a new trial.
We do not doubt that the defendants in the instant case established a prima facie case of deliberate concealment by Huffman under the criteria established in McCoy. Thus, the court was required to hold a posttrial evidentiary hearing. The court held such a hearing. On the basis of the evidence adduced at the hearing, the court found that “Huffman’s failure to respond was an honest mistake. Huffman failed to respond because she honestly believed that she did not have to answer the question.” Opinion and Order filed June 9, 1983 at 6. We find no error in the district court finding.
Huffman testified that she did not intend to conceal information and did not know she was misleading the court. She explained that she concluded for herself that the question was intended to find out only whether her judgment would be affected by a relative’s employment as a police officer. She then concluded that her brother-in-law’s employment would not affect her judgment and therefore did not respond to the question. Huffman was wrong to decide for herself what information was important. Nevertheless, her testimony was sufficient to rebut the defendant’s prima facie case of deliberate concealment. First, defendants failed to establish the third factor listed in McCoy. Huffman claimed that she did not realize before or during the trial that her failure to respond to the question was false or misleading. Second, Huffman’s stated understanding of the question is credible given the entire course of .the voir dire questioning. Prior to the question whether anyone had a close friend or relative who was a law enforcement officer, the government attorney asked the members of the venire whether anyone had prior contact with the Kentucky State Police. Those persons who responded affirmatively were asked whether the contact left them with a particularly favorable or unfavorable impression or whether the contact would affect their judgment if they were chosen to sit on the jury. Transcript of Voir Dire on February 28, 1983 at 27-34. The prospective jurors were then asked by defense counsel whether anyone felt that the testimony of a law enforcement officer was inherently more believable or entitled to greater weight than the testimony of an ordinary citizen. Id. at 56. No one responded affirmatively to this question. Finally, those who responded affirmatively to the question whether anyone had a close friend or relative who was a law enforcement officer were subsequently asked only whether the relationship would influence [225]*225their decision or cause them concern if they were chosen to sit on the jury. They all responded negatively to the second question and were permitted to continue as prospective jurors. Id. at 66-70. This evidence supports the district court’s conclusion that “Huffman’s failure to respond was an honest mistake.” Opinion and Order filed July 9, 1983 at 6.
II
On voir dire, the prospective jurors were asked if they knew any members of the defendants’ families, but no names were mentioned. Tamyra Black did not respond to the question and was selected as a juror. After trial, it was learned that Black and her family had previous contacts with the defendants and members of their families. Black attended high school with Sonja Howard, the daughter of Clifford. Black testified at the posttrial hearing that she became aware of her acquaintance with Clifford’s daughter when Sonja testified at trial. Black claimed that she recognized Sonja from high school days but could recall no specific contact with Sonja and had no basis to form an opinion about her. Transcript of Magistrate’s Hearing on April 29, 1983 at 93-95. Sonja, on the other hand, testified that an incident occurred in high school which caused Black to feel ill-will towards Sonja. Id. at 29-30. Clifford’s son, Franklin Elmo Howard, also attended high school with Black. Black testified that she did not know Franklin from high school. Id. at 96-97. Franklin testified, however, that he had an angry encounter with Black in high school as a result of a fight he had with Black’s high school boyfriend. Id. at 22-27. Black also had a connection with the father of defendant Charles. Black’s brother had negligently destroyed property belonging to the father for which Black’s parents were required to pay damages. Black testified that her father mentioned at the beginning of the trial that he knew one of the defendants but that she did not realize that Charles’ father owned the property destroyed by her brother until after the trial had ended. Id. at 98-102, 117. Finally, Black received an anonymous telephone call during the trial asking if she was a juror on the case. Transcript of District Court Hearing on July 5, 1983 at 33-35.
Defendants do not allege that Black deliberately concealed material information on voir dire. Thus, the McCoy rule of implied bias is inapplicable. Defendants were required to prove actual bias with respect to Black. See McCoy v. Goldston, supra, 652 F.2d at 659. They must “demonstrate ‘the actual existence of such an opinion in the mind of the juror as will raise a presumption of partiality.’ ” Murphy v. Florida, 421 U.S. 794, 800, 95 S.Ct. 2031, 2036, 44 L.Ed.2d 589 (1975). “[A] trial judge’s finding of impartiality should be set aside only upon a showing that prejudice is manifest.” Haney v. Rose, 642 F.2d 1055, 1060 (6th Cir.), cert. denied, 452 U.S. 908, 101 S.Ct. 3036, 69 L.Ed.2d 409 (1981);2 cf. United States v. Pennell, supra, at 532-533 (adopting abuse of discretion standard of review of trial court’s decision not to grant a mistrial for alleged unauthorized contact with jurors); United States v. Sisk, 629 F.2d 1174, 1179 (6th Cir.1980), cert. denied, 449 U.S. 1084, 101 S.Ct. 871, 66 L.Éd.2d 809 (1981) (“Ordinarily a trial judge’s estimate of jury prejudice is accorded ‘the highest degree of respect.’ ”). The district court found Black’s testimony credible and that she sat as an impartial juror. Findings of Fact, Conclusions of Law, and Order filed July 20,1983. Defendants have offered no evidence to rebut the district court’s credibility finding and have not made the very high showing of prejudice necessary for this court to overturn the district court’s determination.
Ill
The indictment in the instant case charged that defendant Charles Shelton, [226]*226with the assistance of unindicted coconspiratory Johnny Howard, deliberately set fire to the residence of Clifford and Harriet Howard. Thereafter, Johnny became a government informant in return for a grant of immunity in the instant case and an agreement that he would not be prosecuted for various other criminal offenses. The government also enrolled Johnny for a while in the federal witness protection program. As a part of Johnny’s agreement with the government, Johnny arranged to meet with defendant Charles and to record their conversations. Johnny was instructed to discuss particular offenses with Charles in an attempt to gather incriminating statements.
Defendants claim that these conversations violated, Charles’ sixth amendment right to the assistance of counsel. Defendants rely primarily on United States v. Henry, 447 U.S. 264, 100 S.Ct. 2183, 65 L.Ed.2d 115 (1980). In Henry, the defendant was indicted for armed robbery and was confined in jail pending trial. Federal agents contacted an inmate confined in the same cellblock as the defendant and offered to pay the inmate for furnishing incriminating statements by the defendant. At trial, the inmate testified about the defendant’s incriminating statements. The Supreme Court held that the government violated the defendant’s sixth amendment right to counsel “[b]y intentionally creating a situation likely to induce [defendant] to make incriminating statements without the assistance of counsel____” Id. at 274, 100 S.Ct. at 2189. The court found three factors important in determining that the government “deliberately elicited” incriminating statements from defendant: (1) the inmate was acting under instructions as a paid informant for the government; (2) the informant “was ostensibly no more than a fellow inmate of [defendant]”; and (3) the defendant was in custody and under indictment at the time he was engaged in conversation by the informant. Id. at 270, 100 S.Ct. at 2186. The Court noted that the defendant’s incarceration, while a “relevant factor,” does not imply a “custody requirement” for sixth amendment rights to attach. Id. at 273 & n. 11, 100 S.Ct. at 2188 & n. 11. Indictment or some formal filing of charges, however, is required before sixth amendment rights are triggered.. Id. at 269-70, 272, 100 S.Ct. at 2186-2188; see also Kirby v. Illinois, 406 U.S. 682, 689, 92 S.Ct. 1877, 1882, 32 L.Ed.2d 411 (1972) (sixth amendment right to counsel attaches “at or after the initiation of adversary judicial proceedings — whether by way of formal charge, preliminary hearing, indictment, information, or arraignment”). Thus, the Court explained in Henry: “It is quite a different matter when the Government uses undercover agents to obtain incriminating statements from persons not in custody but suspected of criminal activity prior to the time charges are filed.” 447 U.S. at 272, 100 S.Ct. at 2188. Preindictment claims are covered by the fourth and fifth amendments. Id.; see also United States v. Muzychka, 725 F.2d 1061, 1069 (3d Cir.), cert. denied, — U.S. —, 104 S.Ct. 2390, 81 L.Ed.2d 348 (1984) (“Until adversary judicial proceedings have commenced, coercive methods of eliciting information from a defendant are governed by Miranda and due process and self-incrimination analyses.”). Defendants raise no fourth or fifth amendment claim before this court.
All of the circuits including this one have held that the sixth amendment right to counsel does not attach until adversary judicial proceedings have commenced. See, e.g., United States v. Muzychka, supra, 725 F.2d at 1068-69; United States v. Franklin, 704 F.2d 1183, 1189 (10th Cir.), cert. denied, — U.S. —, 104 S.Ct. 146, 78 L.Ed.2d 137 (1983); United States v. Hansen, 701 F.2d 1215, 1220 (7th Cir.1983); United States v. Brown, 699 F.2d 585, 589 (2d Cir.1983); United States v. Hamilton, 689 F.2d 1262, 1275 (6th Cir.1982), cert. denied, 459 U.S. 1117, 103 S.Ct. 753, 74 L.Ed.2d 971 (1983). Although there might be room in some cases to question when adversary judicial proceedings have commenced, see, e.g., United States v. Muzychka, supra, 725 F.2d at 1068-69, we find no such question in this case. Charles was [227]*227only a target of the government’s investigation at the time of his conversations with the government informant; he was not under arrest and no indictment or other formal charges had been filed. Thus, his sixth amendment rights had not attached.
IV
The charred remains of the Howard residence were extensively investigated by both state police and the Howards’ insurer. The investigators for both the police and the insurance company were looking for evidence of arson, albeit for different reasons, and the investigators cooperated with each other in the investigation. The police investigator spoke to Clifford Howard before entering the premises but obtained neither express consent nor a warrant to conduct his search. The insurance company investigator entered the premises pursuant to a clause in the insurance contract permitting fire investigations.
At trial, the government attempted to introduce the testimony of the police investigator regarding his investigation. Defendants objected to this testimony as the fruit of an unlawful search because the police had obtained neither consent nor a warrant before entering the property. The trial court sustained defendants’ objection. Excerpted Transcript of Trial on March 1-4, 1983, vol. I at 35-37. The court, however, permitted the government to introduce the testimony of the insurance company investigator. Id. at 56-73. The defendants object to the admission of this testimony. Although a private citizen generally is not subject to the strictures of the fourth amendment, defendants argue that the search of the premises was conducted and directed by the police with the insurance company investigator acting merely as an agent of the government. If the private investigator was acting as “an ‘instrument’ or agent” of the government, then all evidence resulting from the search must be suppressed. Coolidge v. New Hampshire, 403 U.S. 443, 487, 91 S.Ct. 2022, 2049, 29 L.Ed.2d 564 (1971).
We agree with defendants that a consent clause in an insurance contract does not insulate from the fourth amendment a search by a private investigator who acts as an agent of the government to gather incriminating evidence for use in a criminal proceeding. First, the consent contemplated by an insured who agrees to a consent clause is consent to search for evidence relating to the insurer’s liability. An insured does not. contemplate consenting to a search of his home for any and all reasons. Cf. Zap v. United States, 328 U.S. 624, 629, 66 S.Ct. 1277, 1279, 90 L.Ed. 1477 (1946) (assuming that consent to search did not imply consent to seize item). Moreover, because an insured may be or may feel compelled to agree to a consent provisión to obtain the insurance policy, we are not convinced that this consent meets the criteria of voluntariness, see Schneckloth v. Bustamonte, 412 U.S. 218, 248, 93 S.Ct. 2041, 2058, 36 L.Ed.2d 854 (1973) (“[T]he Fourth and Fourteenth Amendments require that [the state] demonstrate that the consent [to search] was in fact voluntarily given, and not the result of duress or coercion, express or implied.”).
We find, however, that the insur — -1 anee company investigator while cooperat- I ing with the police was not acting as an agent of the government. In United States v. Walther, 652 F.2d 788, 792 (9th Cir.1981), the Ninth Circuit found that “two of the critical factors in the ‘instrument or agent’ analysis are: (1) the government’s knowledge or acquiescence, and (2) the intent of the party performing the search.” In the instant case there is no question that the government had knowledge of, and even participated in the search. Nevertheless, where, as here, the intent of the private party conducting the search is entirely independent of the government’s intent to collect evidence for use in a criminal prosecution, we hold that the private party is not an agent of the government. See also United States v. Capra, 501 F.2d 267, 272 n. 4 (2d Cir.1974), cert. denied, 420 U.S. 990, 95 S.Ct. 1424, 43 L.Ed.2d 670 (1975) (“when police are merely assisting a private party, who has au[228]*228thority to search and a legitimate need to do so, ... courts are reluctant to exclude resulting evidence”); cf. Stone v. Wingo, 416 F.2d 857, 860 (6th Cir.1969) (actions of private party attributed to state where “ ‘parties act ... together, in pursuance of some design or in accordance with some scheme’ ”); Metheany v. United States, 365 F.2d 90, 94 (9th Cir.1966) (evidence obtained by a trustee pursuant to a warrant from a bankruptcy court is admissible in a criminal proceeding where the trustee was “primarily motivated by his lawful duty to investigate .the bankrupt’s affairs and collect the assets of the estate, [not] by a desire to commit a wrongful act”). The insurance company investigator was rightfully on the property to determine the liability of the insurance company and his actions are not attributable to the government. Thus, the district court did not err in admitting his testimony.
V
We do find merit in defendant’s final claim. We hold that the admission into evidence against Clifford of the tape recorded conversations between Charles and Johnny3 violated Fed.R.Evid. 802 which [229]*229prohibits the admission of hearsay in the federal courts except as provided by the Federal Rules of Evidence.4
The district court admitted the tapes against Clifford pursuant to Fed.R.Evid. 801(d)(2)(E) which provides: “A statement is not hearsay if ... [t]he statement is offered against a party and is ... a statement by a coconspirator of a party during the course and in furtherance of the conspiracy.” 5 We find that the recorded conversations fail to satisfy the requirements for the admission of coconspirators’ statements. In United States v. Enright, 579 F.2d 980, 986 (6th Cir.1978), this court held that for statements to be admissible pursuant to Rule 801(d)(2)(E) the government must show by a preponderance of the evidence three elements: (1) a conspiracy existed; (2) the defendant against whom the hearsay is admitted was a member of that conspiracy; and (3) the hearsay statement was made in the course and furtherance of the conspiracy. See also United States v. Hamilton, 689 F.2d 1262, 1268 (6th Cir. 1982), cert. denied, 459 U.S. 1117, 103 S.Ct. 753, 74 L.Ed.2d 971 (1983); United States v. Vinson, supra, 606 F.2d at 152. Defendants argue only that the government has failed to establish the third element of Enright.6
We reject defendants’ claim that the recorded statements were not made during the course of the conspiracy. Hearsay statements made after a conspiracy has terminated are not admissible in the federal courts. See Krulewitch v. United States, 336 U.S. 440, 442-43, 69 S.Ct. 716, 717-18, 93 L.Ed. 790 (1949). A conspiracy is deemed to have ended when the last objective sought is achieved, when all co-conspirators have been arrested, or when achievement of the objective has otherwise been rendered impossible. See Wong Sun v. United States, 371 U.S. 471, 490, 83 [230]*230S.Ct. 407, 418, 9 L.Ed.2d 441 (1963); United States v. Hamilton, supra, 689 F.2d at 1268-69. Defendants claim that their alleged conspiracy involved burning down the house and that the conspiracy ended when the house burned. The government responds, and we believe, that the conspiracy alleged in the instant case was one to defraud the insurance company. The final objective of the conspiracy was to obtain the insurance proceeds, and this objective was still being sought when the recorded conversations took place. Thus, the conspiracy had not ended. See also United States v. Xheka, 704 F.2d 974, 985-86 (7th Cir.), cert. denied, — U.S. —, 104 S.Ct. 486, 78 L.Ed.2d 682 (1983) (conspiracy to defraud insurance company does not end when business burns but continues “until defendants obtain the insurance money or abandon their quest”).
Although we conclude that the recorded conversations took place during the course of the conspiracy, we cannot find that the statements were made in furtherance of the conspiracy. The statements did nothing to advance what we have determined to be the remaining objective of the conspiracy, which was to obtain the insurance proceeds. Cf. United States v. Xheka, supra, 704 F.2d at 986 (statements intended to keep coconspirator in the conspiracy were made in furtherance of the conspiracy); United States v. Hamilton, supra, 689 F.2d at 1269-70 (orders to purchase stolen goods placed by coconspirator and statements concerning plans to collect money on orders were made in furtherance of the conspiracy to traffic in stolen goods); United States v. Lang, 589 F.2d 92, 100 (2d Cir.1978) (statement by coconspirator to uncover agent posing as potential buyer of counterfeit bills revealing that another co-conspirator had been arrested with counterfeit money and warning agent to be careful was not in furtherance of conspiracy to distribute counterfeit bills); United States v. Wilson, 490 F.Supp. 713, 717 (E.D.Mich. 1980) (“Narrative declarations ... have never been considered to be made in furtherance of a conspiracy.”), aff.d, 639 F.2d 314 (6th Cir.1981).
The government argues that the statements contained in the taped conversations were directed at avoiding detection. In Krulewitch v. United States, supra, 336 U.S. at 443-44, 69 S.Ct. at 718, the Supreme Court held that declarations made after a conspiracy has terminated in an attempt to prevent detection are not statements made in furtherance of the main conspiracy and are inadmissible under the federal rules. See also Grunewald v. United States, 353 U.S. 391, 401-02, 77 S.Ct. 963, 972, 1 L.Ed.2d 931 (1957); Lutwak v. United States, 344 U.S. 604, 616-18, 73 S.Ct. 481, 488-89, 97 L.Ed. 593 (1953). The government tries to distinguish Krulewitch from the instant case. Avoiding detection, according to the government, was not merely “an implicit subsidiary phase of the conspiracy,” Krulewitch v. United States, supra, 336 U.S. at 443, 69 S.Ct. at 718, but was necessary to achieve the underlying goal of obtaining the insurance proceeds. We might be persuaded if the statements made by Johnny and Charles were directed at avoiding detection by the insurance company. Johnny and Charles, however, discussed only how to avoid detection by the state police. Detection of a continuing illegal conspiracy will always thwart any remaining objectives of the conspiracy. Thus, to accept the government’s position before this court would be to hold that statements directed at avoiding detection are admissible anytime that the conspiracy is continuing. The rule enunciated in Krulewitch, that avoiding detection is not necessarily a part of the main conspiracy, cannot be construed so narrowly. Some link must be established between the attempt to avoid detection and some remaining objective of the conspiracy. The government must still prove both that a “central aim of the conspiracy ... continued in being” and that the declarations directed at “concealment ... were at least partly calculated to further this aim.” Grunewald v. United States, supra, 353 U.S. at 415, 77 S.Ct. at 979. The government has failed to establish that the statements contained in the [231]*231tape recordings were partly calculated to . further the continuing aim of obtaining the insurance proceeds.
The government contends that the “issue” with respect to the course and furtherance requirement is “whether the evidence is basically reliable; whether it is ‘fair’ to permit its introduction; and, whether the evidence (statement) relates in some way to the conspiracy itself.” Brief for the United States at 60. See also United States v. Smith, 520 F.2d 1245, 1247 (8th Cir.1975); 4 J. Weinstein & M. Berger, Weinstein’s Evidence 11801(d)(2)(E)[01], at 801-169 to 172 (1981). We agree. It is because the statements by Charles and Johnny which incriminate Clifford lack any indicia of reliability and because it is unfair to admit the statements as evidence against Clifford that we find them inadmissible. We are most troubled by the fact that one of the conversants was a government informant who was being rewarded for eliciting incriminating statements. We find entirely unreliable any statements made by the informant. We also find unreliable statements elicited from Charles regarding Clifford’s involvement in the conspiracy. Although one is unlikely to adopt incriminating statements concerning oneself, there is no reason to believe that one will necessarily speak out to exculpate another. We are further troubled by the paucity of the evidence (other than the taped conversations) linking Clifford to the conspiracy. The government admits that its case against Clifford was “mostly circumstantial.” See Brief for the United States at 8. Although we are not prepared to hold that the evidence was insufficient as a matter of law to establish Clifford’s involvement in the conspiracy, we cannot disregard the weakness of the evidence in considering the reliability of an alleged co-conspirator’s out-of-court statements. One can imagine a ease in which a person deliberately makes incriminating but untrue statements about another to a known government informant. Cf Krulewitch v. United States, supra, 336 U.S. at 456, 69 S.Ct. at 724 (Jackson, J., concurring) (“Conspirators, long after the contemplated offense is complete, after perhaps they have fallen out and become enemies, may still incriminate each other by deliberately harmful, but unsworn declarations, or unintentionally by casual conversations out of court.”). We must rigorously enforce the standards set forth in Enright to avoid the admission of unreliable hearsay. See United States v. Lang, supra, 589 F.2d at 99100; 4 J. Weinstein & M. Berger, supra, 11 801(d)(2)(E)[01], at 801-73 to 74.
Even if we found that the statements made by Charles were admissible as evidence against Clifford, we would have to reverse Clifford’s conviction because Johnny’s statements were also admitted as evidence against Clifford. Johnny had turned government informant at the time of the taped conversations and thus was no longer a coconspirator. See United States v. Xheka, supra, 704 F.2d at 986 n. 6; United States v. Smith, 623 F.2d 627, 631 (9th Cir.1980). Johnny’s statements were admissible against Charles as adoptive admissions. See Fed.R.Evid. 801(d)(2)(B). There is no basis, however, for admitting Johnny’s statements against Clifford. See United States v. Xheka, supra, 704 F.2d at 986 n. 6. Thus, the district court erred in failing to give a limiting instruction regarding Johnny’s statements. See Lutwak v. United States, supra, 344 U.S. at 618, 73 S.Ct. at 489.
VI
For the foregoing reasons, the conviction of defendant Charles Shelton is affirmed and the conviction of Clifford Howard is reversed and remanded.