In Davis v. Mississippi, the U.S. Supreme Court ruled in 1968 that a mass fingerprinting operation conducted by police without warrants or probable cause was unconstitutional under the Fourth Amendment, which protects against unreasonable searches and seizures. The case arose after Ernest Davis was convicted of rape based on fingerprints obtained during such an operation following a series of rapes in Jackson, Mississippi. Police had rounded up dozens of young black men for questioning and fingerprinting without any specific evidence linking them to the crimes; Davis' prints were matched to those found at one crime scene only after his unlawful detention and interrogation. The court's decision overturned his conviction, establishing that fingerprints taken from individuals not under arrest or suspected of wrongdoing cannot be used as evidence unless they are voluntarily given.

In the dissenting opinion for Davis v. Mississippi, Justice Harlan argued that the majority's decision was too broad and could potentially undermine effective law enforcement. He contended that while individual rights should be protected, it is also essential to consider societal interests in maintaining public safety and order. In his view, fingerprinting does not constitute a significant invasion of personal privacy or dignity compared to other investigative techniques such as search warrants or wiretaps which are considered legal under certain circumstances. Furthermore, he pointed out that fingerprints serve an important function in criminal investigations beyond mere identification - they can provide crucial evidence linking suspects to crimes. Therefore, he believed there should be some flexibility allowing police officers to take fingerprints from individuals during preliminary stages of investigation without necessarily having probable cause for arrest.