In the 1993 case Robert L. Davis v. United States, the Supreme Court ruled that a federal prisoner could not use a writ of habeas corpus to challenge his sentence on grounds that it was enhanced by prior convictions obtained in violation of his right to counsel. The petitioner, Robert L. Davis, argued that two previous state court convictions were unconstitutional because he had been denied effective assistance of counsel and these convictions were used to enhance his current federal sentence under the Armed Career Criminal Act (ACCA). However, the Supreme Court held that unless those earlier convictions are themselves subject to collateral attack while serving for them, they may be relied upon as predicate offenses enhancing a subsequent conviction even if there is an allegation about constitutional infirmity.

In the dissenting opinion for Robert L. Davis v. United States, Justice Blackmun argued that the majority's decision to uphold a warrantless search of an automobile trunk was inconsistent with previous Supreme Court rulings on Fourth Amendment rights and protections against unreasonable searches and seizures. He contended that there were no exigent circumstances or immediate danger present in this case to justify such a search without obtaining a warrant first. Furthermore, he believed that allowing police officers broad discretion to conduct these types of searches could lead to potential abuses of power and violations of citizens' constitutional rights. In his view, the court should have maintained its traditional stance requiring law enforcement officials to obtain warrants before conducting invasive searches unless specific exceptions apply.