In the case of Mark A. Briscoe and Sheldon A. Cypress v. Virginia, 2009, the U.S Supreme Court examined whether a state violates a defendant's rights under the Confrontation Clause of the Sixth Amendment by allowing prosecutors to introduce certificates of analysis showing that a substance was an illegal narcotic without calling as witnesses at trial those who performed or supervised the tests on which these analyses were based. The defendants argued that they had been denied their constitutional right to confront their accusers when such forensic evidence was introduced without any opportunity for cross-examination. However, in its ruling, the court held that it does not violate a defendant’s confrontation clause rights if laboratory analysts do not testify about drug test results so long as those analysts are available for cross-examination at trial.

In the dissenting opinion for Briscoe and Cypress v. Virginia, Justice Scalia argued that the majority's decision undermined a key principle of the Confrontation Clause in criminal trials - that defendants have a right to cross-examine witnesses against them. He contended that allowing lab analysts' reports into evidence without requiring their testimony violated this right. The majority held that if an analyst doesn't testify, another scientist who didn't perform or observe the test could introduce it as long as they were knowledgeable about the testing process used. However, Scalia disagreed with this interpretation because he believed it allowed prosecutors to evade their obligation under Crawford v Washington (2004) which required testimonial statements be subjected to cross-examination at trial unless unavailable and defendant had prior opportunity for cross examination.