State v. Pierce, 548 S.W.3d 900

Officers responded to Pierce's home after he called a suicide hotline and reported auditory hallucinations and suicidal ideation. Pierce consented to officers "check the residence."
Inside, officers observed on a computer screen images suggesting child pornography; they determined images were stored on the hard drive, seized the computer, and later obtained a warrant to search it.
Pierce was charged with one count of possession of child pornography; he moved to suppress evidence arguing his consent was involuntary due to emotional disturbance.
The circuit court found consent involuntary but denied suppression under the exigent-circumstances exception; evidence was admitted and Pierce was convicted after a bench trial.
At sentencing the court misstated the enhanced punishment range as 10–30 years (Pierce’s correct range was 5–30 years for a class B felony as a persistent offender); the court imposed a 15-year term without contemporaneous objection.
On appeal to the Missouri Supreme Court, Pierce challenged denial of suppression and requested resentencing under plain-error review based on the misstated sentencing range.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether evidence should be suppressed because consent was involuntary	Pierce: consent was not voluntary due to emotional disturbance; exclusionary rule should apply	State: even if consent involuntary, exclusion not warranted because officers acted in objectively reasonable good faith; suppression is last resort	Denied suppression; exclusionary rule not applied because police conduct did not show culpable deliberate/reckless behavior and good-faith/isolated negligence mitigates deterrence rationale
Whether sentencing was plain-error because the court misstated the applicable range	Pierce: court misstated range (said 10–30) and thus sentence may have been based on materially false foundation; requests resentencing	State: record shows court sentenced after discussing valid factors (recidivism, danger to children); Pierce failed to show sentence was imposed because of mistaken range	No plain error; affirmed. Court concluded Pierce failed to show the sentence was imposed based on the mistaken range and therefore no manifest injustice

State v. Hyland, 840 S.W.2d 219 (Mo. banc 1992) (consent to search must be freely and voluntarily given)
State v. Johnson, 354 S.W.3d 627 (Mo. banc 2011) (questions of law reviewed de novo)
Hudson v. Michigan, 547 U.S. 586 (2006) (suppression is a last-resort remedy)
Davis v. United States, 564 U.S. 229 (2011) (exclusionary-rule deterrence depends on police culpability; good-faith/isolated negligence undercuts exclusion)
Wraggs v. State, 549 S.W.2d 881 (Mo. banc 1977) (due process requires resentencing when sentence predicated on materially false foundation)
State v. Elam, 493 S.W.3d 38 (Mo. App. 2016) (no resentencing when record shows sentence based on valid considerations, not legal misapprehension)
State v. Baxter, 204 S.W.3d 650 (Mo. banc 2006) (defendant bears burden to show manifest injustice on plain-error review)
State v. Cowan, 247 S.W.3d 617 (Mo. App. 2008) (statute extends only maximum for persistent offender; minimum remains class B minimum)