NACDL

Impact of Recent U.S. Supreme Court Decisions on DUI Defense Law

In its most recent term, the U.S. Supreme Court issued important decisions affecting the constitutional rights of defendants in criminal cases. Although none of the decisions involved a DUI case, several are relevant to DUI defense law. This article addresses three recent Supreme Court decisions — Melendez-Diaz v. Massachusetts,¹ Herring v. United States,² and Arizona v. Gant³ — that will have the greatest impact on DUI defense law.⁴ 

Melendez-Diaz

In Melendez-Diaz v. Massachusetts, the defendant was charged with distributing and trafficking cocaine.⁵ At trial, the prosecution introduced several bags that purportedly contained cocaine into evidence.⁶ 

It also submitted three “certificates of analysis” showing the results of the forensic analysis performed on the seized substances. The certificates reported the weight of the seized bags and stated that the bags “[h]a[ve] been examined with the following results: The substance