The US Supreme Court [official website; JURIST news archive] on Monday ruled [opinion, PDF] 8-1 in Kentucky v. King [Cornell LII backgrounder; JURIST report] that the exigent circumstances rule applies when the police do not act or threaten to act in a way that violates the Fourth Amendment [text]. The case involved a situation where police smelled marijuana outside an apartment door and then knocked on the door announcing their presence. When they heard sounds consistent with the destroying of evidence, they kicked down the door and saw, in plain view, the occupants attempting to destroy the drugs. The Kentucky Supreme Court [official website] held, despite the existence of exigent circumstances, a warrantless arrest was not supported because the police should reasonably have foreseen that their action would create the exigency. However, the US Supreme Court's opinion by Justice Samuel Alito held the police action does not create an exception to the exigent circumstances rule unless it violates the Fourth Amendment. In this case, since knocking on the door was lawful, the exigent circumstances created by the destruction of evidence supported the warrantless arrests. Alito argued that the occupants were under no obligation to open the door: "Occupants who choose not to stand on their constitutional rights but instead elect to attempt to destroy evidence have only themselves to blame for the warrantless exigent-circumstances search that may ensue." Justice Ruth Bader Ginsburg was the lone dissent, arguing that court's ruling violates two Fourth Amendment principles: first, that warrantless arrests inside homes require higher scrutiny, and secondly, that, whenever practical, police should first acquire a warrant from a neutral magistrate.
The Supreme Court's ruling laid to rest a circuit court split with five different tests being used to determine whether the police-created exigency exception applied, with the states developing more. The Kentucky Supreme Court had applied a two-pronged test whereby a warrantless arrest is not allowed when either the police deliberately created the exigency in bad faith or whether it was reasonably foreseeable that the police action would create an exigency.