In the case of John J. Fellers v. United States, 2003, the U.S Supreme Court ruled that police officers violated Fellers' Sixth Amendment right to counsel when they elicited information from him at his home without providing Miranda warnings and then used this information in a subsequent custodial interrogation at jail after giving him these warnings. The court held that once adversarial proceedings have begun against a defendant, he has a right to legal representation during any questioning by law enforcement officials about the charges against him. This ruling overturned an earlier decision by the Eighth Circuit Court of Appeals which had upheld Feller's conviction for conspiracy to distribute methamphetamine on grounds that although initial conversation was unconstitutional, it did not taint later jailhouse statements because they were voluntarily made after receiving Miranda warnings.

In the dissenting opinion for Fellers v. United States, Justice Scalia argued that the majority's decision was inconsistent with prior Supreme Court rulings and failed to properly apply the Sixth Amendment right to counsel. He contended that police officers did not violate Fellers' rights when they questioned him at his home without an attorney present because formal charges had not yet been filed against him. According to Scalia, this initial conversation should be considered "an ordinary investigative interview" rather than a post-indictment interrogation which would require legal representation under the Sixth Amendment. Furthermore, he criticized the majority for creating confusion about when exactly a suspect's right to counsel is triggered during criminal proceedings.