Under the inevitable discovery doctrine, illegally seized evidence may be used where it would have been discovered by the police through lawful means. As the United States Supreme Court has explained, the doctrine “is in reality an extrapolation from the independent source doctrine: Since the tainted evidence would be admissible if in fact discovered through an independent source, it should be admissible if it inevitably would have been discovered.” Murray v. United States, 487 U.S. 533, 539 (1988).
The purpose of the inevitable discovery doctrine is to prevent the setting aside of convictions that would have been obtained without police misconduct. However, courts refuse to apply the doctrine where it is being provoked by the government so as to excuse the failure to obtain a search warrant where the police had probable cause but simply did not attempt to obtain a warrant before the unlawful search at issue. Once government officers have chosen the illegal course, this doctrine does not mean that the government can take a hypothetical “mulligan” so that the case can be decided on the basis a different, legal course of action that the government officers could have but did not take.
In determining whether the inevitable discovery doctrine applies to a particular case, the burden of proof is on the government. The government must prove, by a preponderance of the evidence, that the evidence would have been obtained inevitably through lawful means. “The test, as to the likelihood of eventual discovery, is not one of certainty, but rather of a reasonably strong probability.” People v. Huston, 210 Cal. App. 3d 192, 221 (1989). This process generally involves proof that evidence would have been uncovered by officers in carrying out routine procedures.
The government cannot rely on speculation to meet its burden of proof. “Inevitable discovery involves no speculative elements but focuses on demonstrated historical facts capable of ready verification….” (Nix v. Williams, 467 U.S. 431, 445 n. 5 (1984). In Nix, the case that founded the doctrine, the police found a murder victim’s body by means of a statement unlawfully obtained from the defendant, but they showed that a 200-person search party was drawing near to the body at the tinge it was found through defendant’s statement. The Supreme Court held, that the record was “clear that the search parties were approaching the actual location of the body …, that the volunteer search teams would have resumed the search had Williams not earlier led the police to the body and the body inevitably would have been found.” Id. at 449-450; see also People v. Lamas (1991) 229 Cal.App.3d 560 (where one officer was already working on getting a warrant, which was eventually obtained, the fact that other officers illegally entered the premises and found contraband); United States v. Young, 573 F.3d 711, 722 (9th Cir. 2009) (rejecting inevitable discovery because record contained “nothing more than speculation – not the ‘demonstrated historical facts capable of ready verification’ required by Nix”).