Missouri v. McNeely (2013)
Missouri v. McNeely (2013) was a case decided by United States Supreme Court, on appeal from the Supreme Court of Missouri, regarding exceptions to the Fourth Amendment to the United States Constitution under exigent circumstances.
On October 3, 2010, Tyler McNeely was stopped after a highway patrol officer observed him cross over the centerline while speeding. After failing a field-sobriety test and refusing to blow into a handheld breathalyzer, the officer drove McNeely directly to a medical center. Understanding that by refusing a chemical test his license would be revoked for one year, McNeely continued to refuse. However, at 2:35 a.m., the officer proceeded to instruct the lab technician to conduct the blood test without first obtaining a warrant.
The United States Supreme Court ruled that police must generally obtain a warrant before subjecting a drunken-driving suspect to a blood test, and that the natural metabolism of blood alcohol does not establish an exigency that would justify a blood draw without consent.