Under a grant of use immunity, Frank Zielezinski testified before a federal grand jury about the alleged distribution of cocaine among Phoenix fire fighters. Several months later, that same grand jury indicted Zielezinski on seven counts of possession and distribution of cocaine. Zielezinski argues that a grand jury cannot properly indict a witness who has testified before it under a grant of immunity. Additionally, he argues that prosecutorial misconduct during trial requires reversal. We cannot unquestioningly permit a grand jury that has heard immunized testimony to indict the immunized witness. Thus, we remand for a hearing to determine whether Zielezinski’s indictment was tainted by his testimony. If the indictment is found untainted, the convictions will stand, since they are proper in all other respects.
FACTUAL AND PROCEDURAL BACKGROUND
On August 25, 1982, Randy Waltenburg, a Phoenix fire fighter, was called before a federal grand jury to testify about the alleged distribution of cocaine among Phoenix fire fighters. He testified that he had once obtained cocaine from defendant Frank Zielezinski. Three hours later, Zielezinski testified before the same grand jury. At that time, the prosecutor granted Zielezinski use immunity pursuant to 18 U.S.C. § 6001 et seq. Zielezinski then testified about an incident when he had used cocaine in a Phoenix bar, Graham Central Station, in November 1981. Zielezinski described that incident in some detail to the grand jury, and specified his alleged source for the cocaine, a barmaid at a local lounge. Except for this incident, Zielezinski denied any knowledge of cocaine use or distribution by Phoenix fire fighters. He denied having sold cocaine to Waltenburg, a position which flatly contradicted what the grand jury had heard earlier in the day.
During the next several months, additional witnesses testified before the grand jury. Another Phoenix firefighter, Tim Gallagher, testified that Zielezinski had purchased cocaine from him on at least four separate occasions. These four occasions were all very close in time to both the alleged dealings with Waltenburg and the incident in Graham Central Station.
On November 17, 1982, the grand jury returned an indictment charging eleven persons with numerous crimes related to the possession and distribution of cocaine. Zielezinski was indicted on seven counts. Before trial, a perjury count was dismissed for vagueness. Zielezinski also argued before trial that the remaining counts should be dismissed because the indictments were returned by the same grand jury that had heard his immunized testimony. The government acknowledged that it was prohibited from using Zielezinski’s testimony against him. It submitted to the court grand jury transcripts and case agent reports to establish the independent sources of the evidence upon which the remaining counts were based. No affidavits were *729 offered by the government, and defense counsel was never shown the materials submitted to the court. The court reviewed the transcripts in camera, dismissed count 19 of the indictment, which dealt with a November 1981 cocaine transaction, and concluded that the remaining counts were untainted.
On April 28, 1983, Zielezinski was found guilty of two counts of the lesser included offense of simple possession of cocaine, in violation of 21 U.S.C. § 844(a). He was acquitted of the remaining counts. Zielezinski was sentenced on May 25, 1983, and placed on probation for one year on each count, the periods to run consecutively. Zielezinski appeals these convictions. DISCUSSION
I. INDICTING AN IMMUNIZED WITNESS.
Zielezinski testified before a grand jury under a grant of immunity. That grand jury then indicted him. The government insists that the indictment was untainted, since it rested entirely on sources independent of Zielezinski’s own statements.
See Kastigar v. United States,
A. THE HINTON RULE IS NOT COMPELLED BY THE CONSTITUTION.
Grand juries can properly indict suspects on the basis of hearsay,
see Costello v. United States,
In
Hinton,
a witness gave over 200 pages of testimony before a grand jury and was later indicted by that same jury. From this extreme case,
Hinton
derived a
per se
rule that invalidates an entire class of indictments. The
Hinton
court itself did not rest its rule on a constitutional basis.
United States v. Hinton,
B. ALTHOUGH WE REFUSE TO EXERCISE OUR SUPERVISORY POWER TO ADOPT THE HINTON RULE, ZIELEZINSKI IS ENTITLED TO A HEARING.
“[Gjuided by considerations of justice,”
McNabb v. United States,
318 U.S.
*730
332, 341,
Constitutional requirements can often guide us in the exercise of our supervisory powers.
See United States v. Payner,
In
Costello v. United States,
Second, Justice Black expressed concern about the potential for delay if evidentiary challenges to grand jury indictments could be heard. Justice Black feared that most defendants would insist on “a kind of preliminary trial to determine the competency and adequacy of the evidence before the grand jury.”
Id.
at 363,
Finally, Justice Black argued that evidentiary challenges to indictments were unnecessary because they would “add nothing to the assurance of a fair trial,” at which legal guilt would ultimately be determined.
Id.
at 364,
Like Justice Black's two other arguments, this provides little guidance here. Although some challenges to an indictment can be cured at trial — such as presentation of hearsay or other inadmissible evidence to the grand jury — other improprieties threaten the very integrity of the grand jury itself.
See, e.g., United States v. Kennedy,
The Supreme Court has consistently followed
Costello,
prohibiting challenges to grand jury indictments based on evidence that was obtained improperly. In
Lawn v. United States,
*732
Costello
has also been relied upon to reject challenges to grand jury indictments based on evidence seized in violation of the Fourth Amendment. In
United States v. Calandra,
[T]he validity of an indictment is not affected by the character of the evidence considered. Thus, an indictment valid on its face is not subject to challenge on the ground that the grand jury acted on the basis of inadequate or incompetent evidence; or even on the basis of information obtained in violation of a defendant’s Fifth Amendment privilege against self-incrimination.
In
Hinton,
just this sort of impropriety in the grand jury process was raised. The
Hinton
court reasoned that the government could never meet its heavy burden of proving that the indictment rested upon wholly independent sources where a grand jury heard an immunized witness.
United States v. Hinton,
No other circuit has addressed the question presented in
Hinton,
and there is no Ninth Circuit authority on point.
United States v. Rogers,
Although Zielezinski was given fewer procedural protections than Rogers, he was actually entitled to more. First, in
Rogers,
a person who had heard the defendant’s immunized testimony later improperly repeated it before a grand jury. Since the immunized information was simply recounted by a third person — and not presented by the defendant himself — the grand jury in
Rogers
could not doubt the defendant’s credibility on the basis of his immunized testimony.
Id.
Since this assessment of credibility can taint an indictment,
United States v. Hinton,
Second, Rogers arose in the unique context of a statutory grant of immunity. Section 7(a)(10) of the Bankruptcy Act, 11 U.S.C. § 25(a)(10) (1976), provides use and derivative use immunity in a subsequent criminal case for testimony given by a bankrupt during certain bankruptcy proceedings. This is a far different situation from the usual grant of immunity under 18 U.S.C. § 6002. We cannot expect section 7(a)(10) immunity, granted categorically by legislative fiat, to be carefully tailored to the needs of each individual witness. In contrast, section 6002 immunity is granted during a proceeding “in the hands of a prosecutor who is a lawyer, and who has ample time to consider the appropriate course of action.” Note, Standards for Exclusion in Immunity Cases after Kastigar and Zicarelli, 82 Yale L.J. 171, 179 (1972). It is thus proper for us to hold prosecutors acting under section 6002 to a fairly high degree of care.
Between the flat prohibition of Hinton and the exhaustive affidavits respected in Rogers, there stands a middle ground that accords justice here. We will neither prohibit a grand jury from indicting any witness who testifies before it under a grant of immunity, nor permit prosecutors to shirk their affirmative duty to establish independent sources. Zielezinski is entitled to a hearing at which the government must establish the independent sources upon which the indictment rested. The district court is free to restrict the hearing as necessary to protect grand jury secrecy. This rule best satisfies the considerations underlying the exercise of our supervisory power.
First, requiring a hearing will effectively deter governmental misconduct. Generally, prosecutors should not encourage grand juries to indict an immunized witness. Even if proper, the indictment appears tainted. On a more fundamental level, in this situation courts ought to examine the effect of the prosecutor’s choice on the integrity of the grand jury process. There is no compelling reason for a prosecutor to ask a grand jury to indict an immunized witness. If a prosecutor thinks such an indictment necessary, he should simply assemble a new, untainted, grand jury, and present the evidence to it. This may involve some extra work or time, but it is effort that must be expended to avoid the appearance of impropriety. By granting a hearing to Zielezinski, we provide notice that grand juries should rarely indict immunized witnesses, and require the prosecutor to establish convincingly the independent sources of his evidence.
Additionally, our rule will protect the integrity of the judicial process. We cannot permit convictions to stand where indictments are tainted, and we must satisfy ourselves that prosecutors truly relied upon independent sources. It is entirely proper to require fairly substantial proof in these circumstances.
Kastigar
itself de
*734
scribes the prosecutor’s “affirmative duty” to establish independent sources as a “very substantial protection.”
United States v. Kastigar,
Here, the potential bias created by the prosecutor’s actions does not rise
per se
to constitutional proportions. However, an immunized witness did contradict what other witnesses testified to under oath regarding events very close in time to those underlying the indictment. The government cannot simply provide transcripts to the court,
in camera,
and assume that it has met its
Kastigar
burden. Only a hearing can convincingly establish that the command of the Fifth Amendment has been satisfied.
Cf. United States v. Sears, Roebuck & Co.,
II. PROSECUTORIAL MISCONDUCT.
Zielezinski also complains of certain alleged improprieties by the prosecutor during argument. The general rule is that improprieties in arguments “do not require a new trial unless they are so gross as probably to prejudice the defendant, and the prejudice has not been neutralized by the trial judge.”
United States v. Parker,
CONCLUSION
Prosecutors should avoid permitting grand juries to indict witnesses who have testified before them under grants of immunity. To avoid both violations of grants of immunity and the appearance of impropriety, we grant Zielezinski a hearing at which the government must demonstrate that this indictment rested on sources independent of Zielezinski’s own testimony. If the indictment proves tainted, Zielezinski’s convictions must then be reversed.
REMANDED.
Notes
. Commentators have criticized courts for relying on history for even this limited purpose. Grand juries today operate in a setting far different from the late eighteenth century. These changed circumstances render the historical analogy of dubious value when considering evidential questions. While grand juries have traditionally been permitted to hear inadmissible evidence, ancient grand juries "did not have the assistance of a legally trained prosecutor." Y. Kamisar, W. LaFave & J. Israel, Modern Criminal Procedure 1037 (1980). With a trained prosecutor in the grand jury room, "it is argued, there is ... a greater capacity in the grand jury, assisted by its legal advisor, to distinguish between admissible and inadmissible evidence.” Id. Thus, there is now less reason to permit the presentation of inadmissible evidence to grand juries than there was in the past.
There is another more fundamental reason to question the historical analogy. The harm caused to an individual by an unjust indictment is substantially greater today than it was 200 years ago. “In a system of justice where guilty pleas are the norm and trials are the exception, we can no longer view the prosecutor’s and grand jury’s decisions to indict as mere interim screening decisions.” Arenella, Reforming the Federal Grand Jury and the State Preliminary Hearing to Prevent Conviction Without Adjudication, 78 Mich.L.Rev. 463, 498 (1980). As trials become increasingly uncommon, "we cannot assume that the trial will necessarily deter prosecutors from seeking indictments against defendants whom they could not convict at trial." Id. *731 As a result of these historical changes, it is argued, “the judiciary may have to take more positive action to insure that the grand jury functions effectively.” Johnston, The Grand Jury — Prosecutorial Abuse of the Indictment Process, 65 J.Crim.L. & Criminology 157, 166 (1974).
. Moreover, since the rule we adopt is grounded in this court’s supervisory power rather than in constitutional law, the historical argument becomes irrelevant. Our supervisory choices are grounded in contemporary policy choices; we are not bound to the choices of eighteenth century England.
. The reference to Fifth Amendment violations in
Calandra
was limited to improprieties in the evidence-gathering process.
See Lawn v. United States,
