The attenuation doctrine applies under the Washington Constitution, but it is more narrowly applied than the Fourth Amendment’s. Here is it not satisfied, and there are no intervening circumstances. State v. Mayfield, 2019 Wash. LEXIS 70 (Feb. 7, 2019):
¶62 We have previously indicated that the Wong Sun version of the attenuation doctrine applies as a matter of state constitutional law. E.g., State v. O’Bremski, 70 Wn.2d 425, 428, 423 P.2d 530 (1967). We now explicitly adopt a state attenuation doctrine that is satisfied if, and only if, an unforeseeable intervening act genuinely severs the causal connection between official misconduct and the discovery of evidence. If such a superseding cause is present, then the evidence is not properly viewed as “fruit of the poisonous tree” but, instead, as “fruit” of the superseding cause. In such a case, the State derives no benefit from its officers’ unconstitutional actions. And because a superseding cause must, by definition, be unforeseeable, this narrow attenuation doctrine will not encourage officials to violate article I, section 7 in the hopes of discovering evidence.
¶63 We caution that the attenuation doctrine we adopt today must be narrowly and carefully applied. The State bears the burden of proving that the attenuation doctrine applies and that evidence is admissible despite a violation of article I, section 7. Armenta, 134 Wn.2d at 14. To meet its burden, the State must prove that unforeseen intervening circumstances genuinely severed the causal connection between official misconduct and the discovery of evidence. The State cannot meet its burden by merely showing that there are one or more additional proximate causes of the discovery of evidence. The question of whether intervening circumstances constitute a superseding cause is a highly fact-specific inquiry that must account for the totality of the circumstances, just as it is in the context of tort law. See Maltman v. Sauer, 84 Wn.2d 975, 982, 530 P.2d 254 (1975).
¶64 We also caution that the narrow attenuation doctrine we adopt today is entirely independent of the modern attenuation doctrine used by federal courts. As such, it is irrelevant to our state attenuation doctrine whether suppression in one case will deter similar misconduct in the future. It is also irrelevant whether the officer’s misconduct was merely negligent or was instead flagrant and purposeful. The only question is whether unforeseeable intervening actions genuinely severed the causal connection between official misconduct and the discovery of evidence. If not, then the attenuation doctrine does not apply, and the evidence must be excluded in accordance with article I, section 7 and our state exclusionary rule.
C. The Washington attenuation doctrine is not satisfied here
¶65 Although the trial court did not have the opportunity to rule on Mayfield’s suppression motion in accordance with the narrow attenuation doctrine we adopt today, its findings of fact are sufficient for us to decide the issue as a matter of law. It is plain that the State cannot carry its burden of proving that the causal chain between the official misconduct and the discovery of evidence was genuinely severed by intervening circumstances in this case. We therefore hold that Mayfield’s motion to suppress must be granted.
¶66 As related in the facts section above, Officer Nunes illegally seized Mayfield and requested consent to search his person and his truck while the illegal seizure was ongoing. The requests to search were certainly not unforeseeable intervening circumstances. As found by the trial court, these requests were a purposeful component of “a drug investigation that was not based upon any reasonable and articulable suspicion of actual criminal conduct.” CP at 20.
¶67 Mayfield’s consents to the two searches were also not independent acts of free will sufficient to establish a superseding cause. The State relies heavily on the fact that Mayfield was told he could refuse, limit, or revoke consent to the search of his truck, arguing that these Ferrier warnings made Mayfield’s consent “an informed decision” and thus “‘an independent act of free will’” sufficient to satisfy the attenuation doctrine. Suppl. Br. of Resp’t at 20. We cannot agree.
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¶71 Finally, it is clear that if the state attenuation doctrine is satisfied solely by an unlawfully detained suspect’s consent to search after Ferrier warnings, then the attenuation doctrine would not be a narrow exception to the exclusionary rule at all. To the contrary, it would be broadly applicable to any case where officials remember to use the appropriate “magic words” after violating a person’s article I, section 7 rights. Such a broad rule would do little to protect individual privacy and would thus be inconsistent with article I, section 7 and our state exclusionary rule. It would also distort the purpose of Ferrier, which is to ensure that a person who has not been illegally seized can make an informed decision as to whether to consent to a search of his or her home. Ferrier, 136 Wn.2d at 118. Ferrier warnings were never designed to “purge the taint” of ongoing unlawful seizures for purposes of the attenuation doctrine.
¶72 It is clear from the trial court’s findings that there were no intervening circumstances here that severed the causal connection between Mayfield’s unlawful seizure and the discovery of the money and methamphetamine used against him at trial. Without such intervening circumstances, our state attenuation doctrine cannot apply. Therefore, the evidence must be suppressed.