The defendant, Steven Michael Anderson, was charged with assaulting a police officer during an altercation outside a restaurant in Washington, Iowa. Prior to trial, Anderson filed a discovery motion, Iowa R.Crim.P. 13, which requested several items, including “the criminal records of all prosecution witnesses, if any exist....” The trial court ordered the production of all of the materials requested except the criminal records of the witnesses; this part of Anderson’s request was denied without elaboration.
. Anderson was found guilty of several counts of assault, and he appealed, raising ten issues, including the court’s refusal to compel production of the criminal records. He contended the court’s refusal to order production of the records violated the disclosure rule of
Brady v. Maryland,
The case was heard by the court of appeals, which ruled, in a four-to-two decision, that the criminal records of the prosecution witnesses may be required to be released if they were available to the State and if they contained evidence admissible at trial which was material to Anderson’s case. The court of appeals ordered the case remanded to district court for hearings on those issues but rejected all of the other issues raised. We granted the State’s application for further review on the Brady issue and now vacate the court of appeals decision and affirm the judgment of the district court.
Our rules provide for the discovery by the defendant of his own criminal history, or “rap sheet,” but not that of the State’s witnesses. See Iowa R.Crim.P. 13(2)(a)(3). Anderson argues, however, that production of these records is constitutionally mandated by the familiar Brady rule. The rap sheets were necessary, he claims, to determine if any of the State’s witnesses were subject to impeachment. See Iowa R.Evid. 609(a) (conviction of a crime involving dishonesty or false statement as a basis for impeachment).
The State responds that the
Brady
rule does not mandate production of these records because Anderson has not established a reasonable probability that they would have affected the outcome.
See United States v. Bagley,
I. The Constitutional Issue.
In Brady, the Supreme Court said that the suppression by the prosecution of evidence favorable to an accused upon request violates due process where the evidence is material either to guilt or punishment, irrespective of the good faith or bad faith of the prosecution.
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Brady
involved suppression of exculpatory evidence, while in this case Anderson complains of a suppression of impeachment evidence. For purposes of the
Brady
rule, however, it makes no difference; it applies to both exculpatory and impeachment evidence.
See Bagley,
While it has been observed that “disclosure, rather than suppression, of relevant materials ordinarily promotes the proper administration of criminal justice,”
Dennis v. United States,
In
United States v. Agurs,
The Supreme Court in
Bagley,
however, abandoned the
Agurs
test of what “might have affected the outcome” and adopted a test of “reasonable probability.”
See United States v. O’Dell,
In Bagley, the government’s only two witnesses had signed agreements to furnish information and testimony for a fee. Prior to trial, the defendant filed a motion for disclosure of “any deals, promises or inducements made to witnesses in exchange for their testimony.” The government’s response did not reveal the fact its witnesses had a financial interest in the case. The government further obscured the picture of the witnesses’ interest in the case by its response to the defendant’s request for “[cjopies of all Jencks Act material.” Its response included an affidavit by each of the key witnesses which stated, “I make this statement freely and voluntarily without any threat or rewards, or promises of reward having been made to me in return for it.”
Bagley argued that the failure of the government to respond to his request for production of the fee agreements and the
*234
misleading statement in the affidavits resulted in a denial of due process under the
Brady
rule. In addressing this claim, the Court in
Bagley
adopted the test paralleling that for effective assistance of counsel announced in
Strickland v. Washington,
We find the Strickland formulation of the Agurs test for materiality sufficiently flexible to cover the “no request,” “general request,” and “specific request” cases of prosecutorial failure to disclose evidence favorable to the accused: The evidence is material only if there is a reasonable probability that, had the evidence been disclosed to the defense, the result of the proceeding would have been different. A “reasonable probability” is a probability sufficient to undermine confidence in the outcome.
What evidence presented by Anderson points to a reasonable probability that the undisclosed rap sheets would have resulted in a different outcome of the trial? As
Bagley
itself notes, a “reasonable” probability must be so substantial that it undermines confidence in the outcome of the case.
The burden of proof is on a defendant claiming a
Brady
violation to establish materiality.
See United States v. Boschetti,
We recognize that it is difficult for a defendant who has been denied access to the materials to establish with specificity what effect they might have had on his trial. As one writer has said,
[o]ne can’t imagine the baffling problems of particularizing a need or interest when the party has no access to the evidence he seeks to discover. How does Tantalus particularize that which is out of his sight as well as his reach?
Traynor, Ground Lost and Found in Criminal Discovery, 39 N.Y.U. L. Rev. 228, 230 (1964).
Nevertheless, it is incumbent upon the defendant to make a threshold showing of how the withheld evidence would have affected his case. In the trial court, when Anderson requested the rap sheets of the witnesses, he gave no reasons for his request. He now contends, and we assume, that the reason he wanted them was for possible use for impeachment, that one or more of the potential witnesses might have had a conviction record. Apparently, Anderson made no inquiry about prior convictions of the witnesses, either in their pretrial depositions or in their cross-examination at trial. On appeal, he merely contends that, if the witnesses had such convictions in their backgrounds, the result of his trial might have been different.
A similar argument was made in
United States v. Peltier,
There is a possibility that the jury would have acquitted Leonard Peltier had the records and data improperly withheld from the defense been available to him in order to better exploit and reinforce the inconsistencies casting strong doubts upon the government’s case. Yet, we are bound by the Bagley test requiring that we be convinced, from a review of the entire record, that had the data and records withheld been made available, the jury probably would have reached a different result. We have not been so convinced.
When an assertion of materiality is made in support of a
Brady
argument, a
*235
reviewing court should itself consider any adverse effect that the failure to disclose might have had on the preparation or presentation of the defendant’s case in light of the totality of the circumstances.
Bagley,
Simply alleging, as Anderson has, that he might have found impeaching evidence in the rap sheets and, if so, that it might have aided his defense, does not establish a threshold case of materiality sufficient to justify a remand for a hearing in district court as the court of appeals did in the present case.
See Boschetti,
Even if we were to assume that one or more of the State’s witnesses had had a prior conviction, that fact standing alone would not rise to the level of a reasonable probability of a different result.
Peltier,
In light of the totality of the circumstances, Anderson has not shown that there is a reasonable probability that the outcome would have been different. Because Anderson failed to establish a threshold showing of materiality, we reject his constitutional claim.
II. The Confidentiality Issue.
Great solicitude has been shown by our statutes and cases for the privacy of the persons who are the subjects of criminal history records. Under Iowa Code section 68A.7(9) (1983) (now found as Iowa Code Section 22.7(9) (1987)), criminal history records, such as those sought here, are confidential. They may not be disclosed unless authorized by Iowa Code section 692.3,
Feeney v. Scott County,
In a related case, we held that disclosure may be ordered' “only when there is a reasonable basis for believing that the rap sheet may contain information that is pertinent to the individual’s selection as a juror and that is unlikely to be discovered through voir dire or through juror questionnaires.”
State v. Bessenecker,
the legislature has set a tone of caution against the dissemination of criminal history data except as specified. The legislature restricted the distribution of such data to an exclusive group of agencies and departments, and then provided for its release only under specified conditions.
Anderson’s disclosure request was not even limited to a list of convictions; it asked for the whole record, which would include other, inadmissible evidence. In this regard, it has been said that
[s]ince it is not ordinarily permissible in most jurisdictions to show that a witness has been arrested, or charged with or prosecuted for a criminal offense, or confined in jail or prison, or to inquire about those facts on cross-examination, where no conviction is shown, for the purpose of impairing his credibility, it is not surprising that the courts have usually, although not always, viewed with disfavor attempts by defendants to obtain disclosure of such records about prosecution witnesses. Similarly, in the few cases involving probation or parole records of prosecution witnesses, the courts have denied, or upheld the denial *236 of, defense motions seeking disclosure thereof.
Annotation,
Accused’s Right to Discovery or Inspection of “Rap Sheets” or Similar Police Records About Prosecution Witnesses,
We conclude that the due process claim asserted here must fail and further that the disclosure of the materials requested is prohibited by our confidentiality statutes. We therefore vacate the court of appeals decision and affirm the judgment of the district court.
DECISION OF COURT OF APPEALS VACATED; DISTRICT COURT JUDGMENT AFFIRMED.
Notes
. It should be noted that the portion of the
Bagley
opinion establishing the "reasonable probability" standard, authored by Justice Blackmun, was joined only by Justice O’Connor. The concurring opinion by Justice White, and joined by Chief Justice Burger and Justice Rehnquist, however, approved the "reasonable probability” standard of the Blackmun opinion.
The majority of federal appellate courts have interpreted
Bagley
as establishing a reasonable probability standard.
See, e.g., United States v. Brimberry,
