California v. Trombetta

When stopped in unrelated incidents on suspicion of drunken driving on California highways, each respondent submitted to a Intoxilyzer (breath-analysis) test and registered a blood-alcohol concentration high enough to be presumed to be intoxicated under California law. Although it was technically feasible to preserve samples of respondents' breath, the arresting officers, as was their ordinary practice, did not do so. Respondents were then all charged with driving while intoxicated. Prior to trial, the Municipal Court denied each respondent's motion to suppress the Intoxilyzer test results on the ground that the arresting officers had failed to preserve samples of respondents' breath that the respondents claim would have enabled them to impeach the incriminating test results. Ultimately, in consolidated proceedings, the California Court of Appeal ruled in respondents' favor, concluding that due process demanded that the arresting officers preserve the breath samples.

Held: The Due Process Clause of the Fourteenth Amendment does not require that law enforcement agencies preserve breath samples in order to introduce the results of breath-analysis tests at trial, and thus here the State's failure to preserve breath samples for respondents did not constitute a violation of the Federal Constitution. Pp. 485–491.

(a) To the extent that respondents' breath samples came into the California authorities' possession, it was for the limited purpose of providing raw data to the Intoxilyzer. The evidence to be presented at trial was not the breath itself but rather the Intoxilyzer results obtained from the breath samples. The authorities did not destroy the breath samples in a calculated effort to circumvent the due process requirement of Brady v. Maryland, 373 U.S. 83, and its progeny that the State disclose to criminal defendants material evidence in its possession, but in failing to preserve the samples the authorities acted in good faith and in accord with their normal practice. Pp. 485–488.

(b) More importantly, California's policy of not preserving breath samples is without constitutional defect. The constitutional duty of the States to preserve evidence is limited to evidence that might be expected to play a role in the suspect's defense. The evidence must possess an exculpatory value that was apparent before it was destroyed, and must also be of such a nature that the defendant would be unable to obtain [p480] comparable evidence by other reasonably available means. Neither of these conditions was met on the facts of this case. Pp. 488–490.

142 Cal. App. 3d 138, 190 Cal. Rptr. 319, reversed and remanded.

, delivered the opinion for a unanimous Court. , filed a concurring opinion, post, p. 491.

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.