CALIFORNIA v. TROMBETTA ET AL.

• Citation: 467 U.S. 479,81 L. Ed. 2d 413,104 S. Ct. 2528
• Decision Date: 11 June 1984
• Docket Number: No. 83-305,83-305
• Parties: CALIFORNIA v. TROMBETTA ET AL.
• Court: United States Supreme Court

467 U.S. 479 104 S. Ct. 2528 81 L. Ed. 2d 413 CALIFORNIA v. TROMBETTA ET AL. No. 83-305 SUPREME COURT OF THE UNITED STATES April 18, 1984, Argued June 11, 1984, Decided

CERTIORARI TO THE COURT OF APPEAL OF CALIFORNIA, FIRST APPELLATE DISTRICT 142 Cal. App. 3d 138, 190 Cal. Rptr. 319, reversed and remanded Charles R. B. Kirk, Deputy Attorney General of California, argued the cause for petitioner. With him on the briefs were John K. Van De Kamp, Attorney General, William D. Stein, Assistant Attorney General, and Gloria F. De Hart, Deputy Attorney General John F. DeMeo argued the cause for respondents. With him on the brief were Thomas R. Kenney, J. Frederick Haley, and John A. Pettis. * * Briefs of amici curiae urging reversal were filed for the State of Minnesota et al. by Hubert H. Humphrey III, Attorney General of Minnesota, James B. Early, Special Assistant Attorney General, and Thomas L. Fabel, Deputy Attorney General, Jim Smith, Attorney General of Florida, Linley E. Pearson, Attorney General of Indiana, Edwin Lloyd Tittman, Attorney General of Mississippi, and Mike Greely, Attorney General of Montana; for the Appellate Committee of the California District Attorney’s Association by John R. Vance, Jr.; and for the National District Attorneys Association, Inc., et al. by David Crump, Wayne W. Schmidt, James P. Manak, and Edwin L. Miller, Jr George L. Schraer and Lisa Short filed a brief for the State Public Defender of California as amicus curiae urging affirmance. Briefs of amici curiae were filed for the State of North Carolina by Rufus L. Edmisten, Attorney General, and Isaac T. Avery III, Special Deputy Attorney General; for the County of Los Angeles by Robert H. Philibosian, Harry B. Sondheim, and John W. Messer; and for the California Public Defender’s Association et al. by Albert J. Menaster, William M. Thornbury, and Ephraim Margolin. MARSHALL, J., delivered the opinion for a unanimous Court. O’CONNOR, J., filed a concurring opinion, post, p. 491.

The Due Process Clause of the Fourteenth Amendment requires the State to disclose to criminal defendants favorable evidence that is material either to guilt or to punishment. United States v. Agurs, 427 U.S. 97 (1976); Brady v. Maryland, 373 U.S. 83 (1963). This case raises the question whether the Fourteenth Amendment also demands that the State preserve potentially exculpatory evidence on behalf of defendants. In particular, the question presented is whether the Due Process Clause requires law enforcement agencies to preserve breath samples of suspected drunken drivers in order for the results of breath-analysis tests to be admissible in criminal prosecutions.

I

The Omicron Intoxilyzer (Intoxilyzer) is a device used in California to measure the concentration of alcohol in the blood of motorists suspected of driving while under the influence of intoxicating liquor. n1 The Intoxilyzer analyzes the suspect’s breath. To operate the device, law enforcement officers follow these procedures:

“Prior to any test, the device is purged by pumping clean air through it until readings of 0.00 are obtained. The breath test requires a sample of ‘alveolar’ (deep lung) air; to assure that such a sample is obtained, the subject is required to blow air into the intoxilyzer at a constant pressure for a period of several seconds. A breath sample is captured in the intoxilyzer’s chamber and infrared light is used to sense the alcohol level. Two samples are taken, and the result of each is indicated on a printout card. The two tests must register within 0.02 of each other in order to be admissible in court. After each test, the chamber is purged with clean air and then checked for a reading of zero alcohol. The machine is calibrated weekly, and the calibration results, as well as a portion of the calibration samples, are available to the defendant.” 142 Cal. App. 3d 138, 141-142, 190 Cal. Rptr. 319, 321 (1983) (citations omitted).

In unrelated incidents in 1980 and 1981, each of the respondents in this case was stopped on suspicion of drunken driving on California highways. Each respondent submitted to an Intoxilyzer test. n2 Each respondent registered a blood-alcohol concentration substantially higher than 0.10 percent. Under California law at that time, drivers with higher than 0.10 percent blood-alcohol concentrations were presumed to be intoxicated. Cal. Veh. Code Ann. § 23126(a)(3) (West 1971) (amended 1981). Respondents were all charged with driving while intoxicated in violation of Cal. Veh. Code Ann. § 23102 (West 1971) (amended 1981).

Prior to trial in Municipal Court, each respondent filed a motion to suppress the Intoxilyzer test results on the ground that the arresting officers had failed to preserve samples of respondents’ breath. Although preservation of breath samples is technically feasible, n3 California law enforcement officers do not ordinarily preserve breath samples, and made no effort to do so in these cases. Respondents each claimed that, had a breath sample been preserved, he would have been able to impeach the incriminating Intoxilyzer results. All of respondents’ motions to suppress were denied. Respondents Ward and Berry then submitted their cases on the police records and were convicted. Ward and Berry subsequently petitioned the California Court of Appeal for writs of habeas corpus. Respondents Trombetta and Cox did not submit to trial. They sought direct appeal from the Municipal Court orders, and their appeals were eventually transferred to the Court of Appeal to be consolidated with the Ward and Berry petitions. n4

The California Court of Appeal ruled in favor of respondents. After implicitly accepting that breath samples would be useful to respondents’ defenses, the court reviewed the available technologies and determined that the arresting officers had the capacity to preserve breath samples for respondents. 142 Cal. App. 3d, at 141-142, 190 Cal. Rptr., at 320-321. Relying heavily on the California Supreme Court’s decision in People v. Hitch, 12 Cal. 3d 641, 527 P. 2d 361 (1974), the Court of Appeal concluded: “Due process demands simply that where evidence is collected by the state, as it is with the intoxilyzer, or any other breath testing device, law enforcement agencies must establish and follow rigorous and systematic procedures to preserve the captured evidence or its equivalent for the use of the defendant.” 142 Cal. App. 3d, at 144, 190 Cal. Rptr., at 323. n5 The court granted respondents Ward and Berry new trials, and ordered that the Intoxilyzer results not be admitted as evidence against the other two respondents. The State unsuccessfully petitioned for certiorari in the California Supreme Court, and then petitioned for review in this Court. We granted certiorari, 464 U.S. 1037 (1984), and now reverse.

II

Under the Due Process Clause of the Fourteenth Amendment, criminal prosecutions must comport with prevailing notions of fundamental fairness. We have long interpreted this standard of fairness to require that criminal defendants be afforded a meaningful opportunity to present a complete defense. To safeguard that right, the Court has developed “what might loosely be called the area of constitutionally guaranteed access to evidence.” United States v. Valenzuela-Bernal, 458 U.S. 858, 867 (1982). Taken together, this group of constitutional privileges delivers exculpatory evidence into the hands of the accused, thereby protecting the innocent from erroneous conviction and ensuring the integrity of our criminal justice system.

The most rudimentary of the access-to-evidence cases impose upon the prosecution a constitutional obligation to report to the defendant and to the trial court whenever government witnesses lie under oath. Napue v. Illinois, 360 U.S. 264, 269-272 (1959); see also Mooney v. Holohan, 294 U.S. 103 (1935). But criminal defendants are entitled to much more than protection against perjury. A defendant has a constitutionally protected privilege to request and obtain from the prosecution evidence that is either material to the guilt of the defendant or relevant to the punishment to be imposed. Brady v. Maryland, 373 U.S., at 87. Even in the absence of a specific request, the prosecution has a constitutional duty to turn over exculpatory evidence that would raise a reasonable doubt about the defendant’s guilt. United States v. Agurs, 427 U.S., at 112. The prosecution must also reveal the contents of plea agreements with key government witnesses, see Giglio v. United States, 405 U.S. 150 (1972), and under some circumstances may be required to disclose the identity of undercover informants who possess evidence critical to the defense, Roviaro v. United States, 353 U.S. 53 (1957).

Less clear from our access-to-evidence cases is the extent to which the Due Process Clause imposes on the government the additional responsibility of guaranteeing criminal defendants access to exculpatory evidence beyond the government’s possession. On a few occasions, we have suggested that the Federal Government might transgress constitutional limitations if it exercised its sovereign powers so as to hamper a criminal defendant’s preparation for trial. For instance, in United States v. Marion, 404 U.S. 307, 324 (1971), and in United States v. Lovasco, 431 U.S. 783, 795, n. 17 (1977), we intimated that a due process violation might occur if the Government delayed an indictment for so long that the defendant’s ability to mount an effective defense was impaired. Similarly, in United States v. Valenzuela-Bernal, supra, we acknowledged that the Government could offend the Due Process Clause of the Fifth Amendment if, by deporting potential witnesses, it diminished a defendant’s opportunity to put on an effective defense. n6 458 U.S., at 873.

We have, however, never squarely addressed the government’s duty to take affirmative steps to preserve evidence on behalf of criminal defendants. The absence of doctrinal development in this...