California v. Trombetta

Summary

The Court held that the Fourteenth Amendment does not require law-enforcement agencies to preserve breath samples before admitting breath-analysis results in a drunken-driving prosecution. The constitutional preservation duty is limited to evidence whose exculpatory value was apparent before destruction and for which the defendant could not obtain comparable evidence by reasonably available means; the breath samples failed both requirements. The Court therefore reversed and remanded the judgment excluding the test results.