Probation Waivers vs. Co‑Occupant Objection: State v. Horn and the Limits of Georgia v. Randolph in Idaho

I. Introduction

In State v. Horn, the Idaho Supreme Court confronted two recurring and important criminal procedure issues:

• How far a probationer’s Fourth Amendment waiver reaches when the probationer shares a home with a non‑probationer who explicitly refuses entry at the door; and
• When a co‑defendant’s out‑of‑court confession, captured on body‑camera, can be used in a joint trial without violating the Confrontation Clause.

The case arises from a probation residence check and search of a shared bedroom in Boise, occupied by Kaylee Horn (the appellant) and Richard Noyes, both of whom were on felony probation and had signed broad Fourth Amendment waivers. During a residence verification for Noyes, probation officer Jaime Juarez entered the home over Horn’s attempt to shut the door and later discovered methamphetamine and drug paraphernalia in the couple’s shared bedroom. Horn moved to suppress, claiming the entry and search violated the Fourth Amendment under Georgia v. Randolph, because she objected at the threshold. She also sought to exclude a body‑camera recording of Noyes stating that “we” were using the paraphernalia, contending this violated Bruton and her Sixth Amendment right to confrontation.

The Idaho Supreme Court:

• Affirmed denial of the motion to suppress, holding that a probationer’s Fourth Amendment waiver authorizing searches of his residence is sufficient to permit warrantless entry and search, even over a co‑tenant’s contemporaneous objection, so long as officers reasonably limit the search to areas under the probationer’s control or joint control; and
• Found that admission of Noyes’ recorded “we” statement violated Bruton, but held the error harmless beyond a reasonable doubt because of Horn’s own incriminating statements and other evidence of joint possession.

In doing so, the Court declines to extend the U.S. Supreme Court’s co‑occupant‑objection rule in Randolph to the probation‑search context and clarifies how Miranda, Doyle, adoptive admissions, and the Confrontation Clause interact when codefendants are jointly interrogated and tried.

II. Factual and Procedural Background

A. The Probation Status of Horn and Noyes

Both Horn and Noyes were on felony probation following guilty pleas to drug‑possession charges. Each had signed a probation agreement with the Idaho Department of Correction (IDOC) containing a broad Fourth Amendment waiver:

SEARCH: I consent to lawful searches by any agent of the IDOC and understand that searches may be conducted of my person, residence, vehicle, personal property, and other real property or structures owned or leased by me, or for which I am the controlling authority. I hereby waive my Fourth Amendment rights under the Idaho and United States Constitutions concerning searches.

Noyes was supervised by IDOC probation officer Jaime Juarez. Horn had previously had her own probation revoked, served a “rider” (Idaho’s retained‑jurisdiction program), and then had probation reinstated, also subject to a Fourth Amendment waiver.

B. The Residence Verification and Entry

In August 2022, Juarez went to a Boise residence to verify it as Noyes’ home. The residence was occupied by both Noyes and Horn. The sequence of events is critical:

1. Juarez knocked; Horn answered the door.
2. Horn told him Noyes was home and then tried to close the door on him.
3. Juarez, then unaware Horn herself was on probation, prevented the door from closing by placing his foot in the doorway and entered.
4. Horn ran downstairs to the bathroom where Noyes was showering; Juarez followed.
5. After interacting with Noyes and Horn, Juarez learned that they shared the downstairs bedroom.

Before entering the bedroom, in Horn’s presence, Juarez asked Noyes whether there was anything in the room that would get them in trouble. Noyes said there was a box on the bed with “possible drugs and paraphernalia.” Horn indicated the same. Inside the room, Juarez found:

• A box on the bed containing needles and small baggies with a crystal‑like substance; and
• Additional paraphernalia on both sides of the bed: another box on Noyes’ side, and a box on the floor next to the nightstand on Horn’s side, as each identified to Juarez.

Both Horn and Noyes initially disclaimed ownership of the box on the bed, saying they were cleaning the room. Juarez called in Boise Police Officer Sell, who field‑tested the syringes, secured the evidence, and later learned the substance was methamphetamine. Sell read Horn and Noyes their Miranda rights and questioned them further, capturing the interaction on body‑camera.

C. Charges, Motion to Suppress, and Joint Trial

Horn was charged with:

• Possession of a controlled substance (methamphetamine);
• Possession of drug paraphernalia; and
• A sentencing enhancement under Idaho Code § 37‑2739 (persistent violator / repeat controlled‑substance conviction).

Horn moved to suppress the drug and paraphernalia evidence, arguing:

• Her attempt to close the door was an express refusal of consent under Georgia v. Randolph, rendering Juarez’s warrantless entry and subsequent search unreasonable; and
• Her own probationary waiver could not retroactively validate an otherwise unconstitutional entry because Juarez did not know she was on probation at the time, citing State v. Maxim.

The district court denied the motion, relying largely on State v. Phipps for the proposition that officers may detain all occupants during a lawful probation search and treating Juarez’s entry as consistent with that authority. Horn and Noyes were tried jointly. At trial, over defense objection, the court admitted Officer Sell’s body‑camera footage, which included Noyes’ statement that the paraphernalia in the room was “paraphernalia shit that we [were] using.” The jury convicted Horn on both possession counts, and she admitted the prior drug conviction supporting enhancement. She received a six‑year sentence (1.5 years fixed) for the methamphetamine count and time served for paraphernalia.

Horn appealed, raising two issues:

1. Whether the district court erred in denying her motion to suppress the evidence from the search; and
2. Whether admitting Noyes’ statements from the body‑camera video violated her Sixth Amendment confrontation rights under Bruton v. United States.

III. Summary of the Opinion

The Idaho Supreme Court, in an opinion by Chief Justice Bevan, affirmed Horn’s convictions but clarified and, in some respects, corrected the district court’s analysis.

A. Fourth Amendment / Motion to Suppress

The Court:

• Disapproved the district court’s reliance on State v. Phipps to justify Juarez’s entry, noting that Phipps deals with the authority to detain all occupants during a lawful probation search, not the authority to enter a residence in the first instance.
• Rejected Horn’s argument that Georgia v. Randolph invalidated the search because she objected at the door. The Court expressly declined to extend Randolph to the probation‑search context.
• Distinguished Maxim, explaining that the State was not relying on Horn’s own waiver (which Juarez did not know about at entry), but on Noyes’ waiver, which Juarez clearly knew about as Noyes’ supervising officer.
• Held that Noyes’ probationary Fourth Amendment waiver authorized Juarez to enter and search Noyes’ residence—even though Horn, a co‑occupant, attempted to refuse entry—because a co‑tenant who chooses to live with a probationer has a reduced expectation of privacy and assumes the risk that probation officers will conduct warrantless searches of shared areas.
• Emphasized limits: co‑tenants do not forfeit all Fourth Amendment rights. Officers must confine their search to areas reasonably believed to be under the probationer’s control or shared control. Here, the search was confined to the shared bedroom and shared containers, consistent with State v. Barker.

In short, the Court established that in Idaho, a valid probationary search of a probationer’s shared residence is not rendered unreasonable simply because a non‑probationer co‑occupant objects at the door.

B. Sixth Amendment / Bruton, Adoptive Admissions, and Harmless Error

On the confrontation issue, the Court:

• Agreed that admission of Noyes’ “paraphernalia shit that we [were] using” statement on the body‑camera video violated Bruton as to Horn. Because Horn had already been Mirandized and had not yet answered questions when Noyes made this statement, her silence could not be treated as an “adoptive admission” consistent with due process concerns under Doyle v. Ohio.
• Nevertheless held the Bruton error harmless beyond a reasonable doubt, given the weight of other evidence, including:
  • Horn’s own admissions that there was “a box of paraphernalia and methamphetamine” in the bedroom;
  • Her explanation that she and Noyes were “just in the process” of cleaning the room and getting things ready to throw away; and
  • Physical evidence and corroborating testimony that she shared the bedroom and knew where the paraphernalia and methamphetamine were located.

Accordingly, although the Court found a constitutional evidentiary error, the conviction stood.

IV. Detailed Analysis

A. The Fourth Amendment and Probation Waivers

1. The Precise Legal Question

The central Fourth Amendment question was:

When a probationer has signed a broad Fourth Amendment waiver authorizing searches of his residence, may a probation or law‑enforcement officer lawfully enter and search that residence over the contemporaneous objection of a co‑occupant, or does Georgia v. Randolph prohibit reliance on the probationer’s consent?

A related issue, though effectively resolved by Maxim, was whether Horn’s own waiver—unknown to Juarez at entry—could retroactively justify the intrusion. The Court adhered to its prior rule that an unknown waiver cannot cure an otherwise unconstitutional entry and therefore analyzed the search solely under Noyes’ waiver and status.

2. Precedents on Probation Searches and Co‑Occupant Authority

The Court’s reasoning chiefly rested on earlier Idaho precedent and federal co‑occupant consent doctrine.

a. United States v. Matlock and the Assumption of Risk

In United States v. Matlock, 415 U.S. 164 (1974), the U.S. Supreme Court held that consent to search a shared premises may come from a third party who has “common authority” over the property. That authority:

rests on mutual use of the property by persons generally having joint access or control for most purposes, so that it is reasonable to recognize that any of the co‑inhabitants has the right to permit the inspection… and that the others have assumed the risk that one of their number might permit the common area to be searched.

Idaho courts have long relied on this “assumption of risk” framework for co‑occupant consent.

b. State v. Barker (Idaho 2002)

In State v. Barker, 136 Idaho 728, 40 P.3d 86 (2002), a parolee (Tate) had signed a waiver similar to Noyes’. Police believed he lived at Barker’s apartment and, after confirming that he was residing there, entered and searched. They found a fanny pack with methamphetamine and a title with both Tate’s and Barker’s names.

The Idaho Supreme Court held:

• Tate’s waiver extended to any residence where he lived; and
• Because Tate and Barker occupied the master bedroom, Tate had “common authority” over it sufficient to consent to a search of that room, though not over items exclusively under Barker’s control.

The Court in Horn imported this logic directly, essentially substituting Noyes and Horn for Tate and Barker. Noyes’ waiver authorized IDOC agents to search his residence. Once Juarez learned that this residence was Noyes’ home and that he and Horn shared the bedroom, Juarez was entitled—under Barker—to enter and search the shared bedroom and shared containers.

C. State v. Misner (Idaho Ct. App. 2000)

State v. Misner, 135 Idaho 277, 16 P.3d 953 (Ct. App. 2000), further developed the principle that a probationer’s waiver can incidentally intrude on cohabitants’ privacy. There, officers searched a home believed to be the probationer’s residence and, in the process of verifying he was not hiding, saw paraphernalia and obtained additional drugs from the non‑probationer homeowner (Misner).

The Court of Appeals upheld the search, reasoning that:

• Officers reasonably believed the probationer resided there and had common authority; and
• To hold otherwise would compromise the “value and effectiveness of supervised probation” because probationers could evade oversight by residing with non‑probationers.

Misner thus highlights the institutional interest—echoed in Horn—in preserving meaningful probation supervision even when probationers live with others.

d. State v. Johnson (Idaho 1986)

In State v. Johnson, 110 Idaho 516, 716 P.2d 1288 (1986), the Court recognized that co‑occupants who reside with a probationer or parolee may have a reduced expectation of privacy in shared spaces because they assume the risk of searches arising from the probationer’s status. Horn explicitly cites Johnson for that proposition.

e. State v. Gawron, Phipps, and Maxim

• State v. Gawron, 112 Idaho 841, 736 P.2d 1295 (1987), treated probation searches as a kind of consent search based on the probationer’s waiver; the State relied on Gawron in the trial court, and the Supreme Court noted that this framed the issue under a consent‑based analysis (rather than “totality of circumstances”).
• State v. Phipps, 166 Idaho 1, 454 P.3d 1084 (2019), held that officers have “categorical authority” to detain all occupants incident to a lawful probation or parole search, but it expressly did not decide when officers may lawfully enter, because entry was undisputed there. Horn clarifies that Phipps does not itself authorize entry.
• State v. Maxim, 165 Idaho 901, 454 P.3d 543 (2019), held that a Fourth Amendment waiver cannot retroactively justify an otherwise unreasonable home entry if officers were unaware of the waiver at the time of the entry. Horn correctly invoked Maxim to argue that her own unknown waiver could not salvage Juarez’s entry, and the Court agreed—but pointed out it was not relying on Horn’s waiver at all, only Noyes’ known waiver.

3. Georgia v. Randolph and Why It Does Not Control

In Georgia v. Randolph, 547 U.S. 103 (2006), police sought consent to search a marital home. The wife consented, but Randolph, physically present at the door, expressly refused. The Court, emphasizing “widely shared social expectations,” held:

a warrantless search of a shared dwelling for evidence over the express refusal of consent by a physically present resident cannot be justified as reasonable as to him on the basis of consent given to the police by another resident.

Horn relied heavily on Randolph, arguing:

• Her attempt to slam the door in Juarez’s face was a clear refusal to consent, satisfying Randolph’s “express refusal” requirement; and
• Therefore, any consent by Noyes (probationary or otherwise) could not validate the subsequent search as to her.

The Court accepted that Horn’s attempt to shut the door was a genuine and sufficient refusal under Randolph, citing State v. Reed (Wis. 2018) for the proposition that trying to close the door is as clear a “do not enter” signal as one can give. But the Court held Randolph does not apply in the probation‑waiver setting.

The key distinctions:

• In Randolph, neither occupant was on probation; the search was defended only under the consent exception, grounded in private social expectations.
• The U.S. Supreme Court’s probation and parole search cases—Griffin v. Wisconsin, United States v. Knights, and Samson v. California—do not treat probation searches as ordinary consent searches. They rest on “special needs” or “totality of the circumstances” balancing, recognizing diminished expectations of privacy and substantial government interests in supervision.
• Idaho’s own approach (at least as presented below in this case) still frames probation searches in consent‑like terms, but the Court emphasized that here the justification is the legal agreement—the probationer’s signed waiver—not ordinary social custom about houseguests and visitors.

The Court thus held that the Randolph rule, which is explicitly limited and has been narrowly interpreted (Fernandez v. California), should not be “extended” to override a probation‑waiver search. As the Court put it, the state’s ability to conduct probationary searches:

is not dependent on social custom. It is grounded in the legal agreement between the state and the probationer, totally devoid of any justification grounded in social custom.

To extend Randolph would effectively allow a non‑probationer roommate to nullify a core condition of probation simply by answering the door and objecting—an outcome the Court found incompatible with the rationale of probation supervision.

4. Co‑Tenant’s Reduced Expectation of Privacy and Assumption of Risk

Relying on Barker, Misner, Johnson, and Matlock, the Court articulated a clear principle:

• A person who chooses to live with a probationer who has waived Fourth Amendment protections assumes the risk that officers will conduct warrantless searches of the shared home; and
• This choice necessarily entails a reduced expectation of privacy in shared spaces, because the co‑tenant knows (or is charged with knowing) that the probationer’s status allows supervisors to inspect those areas.

The Court presented a practical hypothetical: if a probationer could always be shielded by a non‑probationer roommate who answers the door and refuses entry, then “the entire purpose of probationary waivers would be eviscerated.” This echoes the concern expressed in Misner and in federal cases such as United States v. Harden, 104 F.4th 830 (11th Cir. 2024), which the Court cited for the proposition that an otherwise reasonable probation‑home search is not rendered unreasonable merely because a co‑occupant knows of the probation.

The Court also noted circumstantial evidence that Horn likely knew Noyes was on probation and subject to searches—e.g., her immediate dash to the bathroom where he was showering when the officer blocked the door—underscoring that her expectation of privacy was diminished.

5. Limits: Co‑Tenants Do Not Lose All Fourth Amendment Rights

Crucially, the Court was careful to preserve some Fourth Amendment protection for non‑probationer co‑tenants. It explicitly stated:

co‑tenants do not lose their Fourth Amendment rights just because they live with a probationer. A subsequent search must be limited to those areas police officers reasonably believe are under the control of the probationer or areas where the probationer and a co‑occupant maintain shared control.

This mirrors the line drawn in Barker and in cases from other jurisdictions such as People v. Bursch and State v. Davis. Practically, this means:

• Shared spaces (living room, shared bedroom, common bathroom, kitchen) are generally searchable under the probationer’s waiver.
• Areas or containers under the exclusive control of the non‑probationer (for example, a clearly private bedroom, a locked safe accessible only to the non‑probationer) remain protected and typically cannot be searched solely based on the probationer’s waiver, absent independent justification.

Here, Horn did not argue that particular areas of the bedroom or specific containers were exclusively hers or beyond Noyes’ control. The shared bedroom and the boxes of paraphernalia were jointly used spaces, and she herself directed Juarez to the box on the bed and to additional paraphernalia on her side of the bed. Thus, even under the Court’s limiting principle, the search fell within permissible scope.

6. Procedural Nuance: Preservation of the “Totality of Circumstances” Argument

A notable procedural aspect concerns the analytical framework for probation searches. The State, on appeal, tried to argue that under federal cases like Knights and Samson, the search should be upheld as reasonable under a general “totality of the circumstances” approach, not just under the consent/waiver theory. The Court held this argument unpreserved:

• In the trial court, the State had relied on Gawron and framed the search as lawful under the consent exception based on Noyes’ waiver.
• An argument refined on appeal is permissible, but an entirely new analytical basis is not. The shift from a consent theory to a totality‑of‑circumstances theory was deemed a “different horse,” not just a groomed one.

Thus, while federal law allows probation searches to be justified under varied rationales, Horn is decided squarely within Idaho’s existing consent‑waiver framework, leaving for another day whether Idaho will more fully embrace the Knights/Samson style analysis.

B. The Sixth Amendment, Bruton, and Adoptive Admissions

1. The Body‑Camera Evidence

The second major issue centered on admission of Officer Sell’s body‑camera footage, which captured a joint post‑Miranda interrogation on the couch after the search. The critical statements were:

• Sell: “So you guys are both living in that room together?”
• Noyes: “Yes.”
• Sell: “What’s in that room?”
• Noyes: “Paraphernalia shit that we [were] using.”
• Horn: We were “just in the process of like going through the room and making sure like, it was 100% good. That’s why everything was right there, cause like we’re just getting everything ready to throw away.”
• Regarding a bag with crystals, Horn: “Like I said, it was just in the room and we were throwing everything away.”

At trial, the State sought to offer the entire body‑camera video in its case‑in‑chief in a joint trial against Horn and Noyes. Horn objected under Bruton v. United States, which bars the admission of a non‑testifying co‑defendant’s facially incriminating confession in a joint jury trial when used against another defendant.

The State argued two points:

1. Horn had effectively “adopted” Noyes’ “we” statement, making it her own admission and obviating any Confrontation Clause problem.
2. Even if there were error, it was harmless given other evidence.

2. Adoptive Admissions and the Confrontation Clause

Under Idaho Rule of Evidence 801(d)(2)(B), a statement is not hearsay if:

it is one the party manifested that it adopted or believed to be true.

In State v. Moses, 156 Idaho 855, 332 P.3d 767 (2014), the Court set out a two‑part test for adoptive admissions:

1. Was the statement such that, under the circumstances, an innocent person would normally be induced to respond?
2. Are there sufficient foundational facts from which the jury could infer that the defendant heard, understood, and acquiesced in the statement?

Many jurisdictions hold that if a defendant adopts someone else’s statement, that statement becomes the defendant’s own for Confrontation Clause purposes; thus, no Bruton problem arises because the “witness against the defendant is the defendant himself.”

Here, the State contended that:

• Horn’s silence in the immediate aftermath of Noyes’ “we” statement manifested adoption;
• Alternatively, her later use of “we” in explaining that they were cleaning up the room showed that she believed Noyes’ “we” usage (joint involvement) to be true.

3. Miranda, Doyle, and “Selective Silence”

The defense responded that Horn had just been read Miranda warnings and had an explicit right to remain silent; using her silence to infer adoption would conflict with due process principles articulated in Doyle v. Ohio, 426 U.S. 610 (1976), which held that post‑Miranda silence is “insolubly ambiguous” and cannot be used against a defendant to impeach later testimony.

The Idaho Supreme Court took a nuanced approach:

• It acknowledged authority (e.g., Doyle, Ferrara (Mass. App. Ct.)) that silence after Miranda warnings generally cannot be treated as an admission.
• It also recognized a line of “selective silence” cases (e.g., Ex parte Salinas, Talton, McReavy, Bowman) holding that if a defendant, after receiving Miranda warnings, chooses to answer some questions without expressly re‑invoking the right to remain silent, then they may lose Doyle protection for that period of selective silence.
• Consistent with Salinas v. Texas and Minnesota v. Murphy, the Court adopted the principle that a defendant must affirmatively invoke the privilege against self‑incrimination; mere silence is typically insufficient.

The Court then announced a clear rule for Idaho:

a defendant waives the right to remain silent by selectively answering questions after having been informed of Miranda rights, and such a defendant cannot rely on the protections found in Doyle unless the defendant affirmatively reasserts the right to remain silent.

However, timing was everything. The incriminating “we” statement by Noyes occurred before Horn chose to answer any questions. Thus:

• At the time Noyes spoke, Horn had not yet waived her right to remain silent by speaking; and
• Her silence in that moment remained protected post‑Miranda silence under Doyle, from which an adoptive admission could not fairly be inferred.

Because Horn did not adopt Noyes’ statement, the statement remained a classic Bruton‑type co‑defendant confession being used against her in a joint trial without cross‑examination. The Court therefore held that admission of the body‑camera footage, insofar as it included Noyes’ “we” statement, violated the Confrontation Clause.

4. Harmless‑Error Analysis

Having found a constitutional error, the Court turned to harmless error analysis under Yates v. Evatt and Idaho’s own standard in State v. Garcia. The question: Did the erroneous admission “contribute to the ensuing verdict,” or was it unimportant in light of the entire record?

Key factors supporting harmlessness:

• She told him there would be a box of paraphernalia and methamphetamine in the bedroom. She volunteered that she and Noyes were cleaning up and getting things “ready to throw away,” providing a narrative that acknowledged knowledge and control over the contraband.
• Horn’s statements to Sell (apart from Noyes’ “we”): She repeated that they were cleaning the room, that the paraphernalia and crystals were present, and that they were in the process of disposing of them.
• Shared control of the bedroom: Testimony and physical evidence (e.g., men’s and women’s clothing) confirmed that Horn and Noyes shared the bedroom.
• Horn’s guidance to officers: She identified locations—on the bed and beside her nightstand—where paraphernalia would be found, underscoring her awareness and control.

The Court concluded that Noyes’ “we” statement added little that was not already established by Horn’s own admissions and the physical evidence. Even excising the body‑camera portion containing Noyes’ “we” statement, the record still compelled a finding that Horn knowingly possessed the methamphetamine and paraphernalia. Thus, the error did not meaningfully affect the jury’s verdict and was harmless beyond a reasonable doubt.

V. Complex Concepts Simplified

1. Probation Fourth Amendment Waiver

A probationer often must agree, as a condition of probation, to allow warrantless searches by probation officers (and sometimes other law enforcement) of:

• His or her person;
• Residence;
• Vehicles; and
• Personal property and other controlled premises.

This is a conditional bargain: in exchange for remaining in the community rather than going to prison, the probationer accepts a reduced expectation of privacy. In Idaho, the waiver is treated largely as a form of advance consent authorizing searches consistent with its terms.

2. Co‑Occupant Consent and Assumption of Risk

When multiple people share a home, each generally has authority to consent to a search of common areas (e.g., living room, shared bedroom). Under Matlock, if one co‑occupant consents, the others are assumed to have borne the risk that this could occur.

Georgia v. Randolph carved out a narrow exception: if a co‑occupant is physically present and expressly refuses consent at the door, that refusal trumps the other’s consent for that specific type of “consent search”. Horn holds that this exception does not extend to probation‑waiver searches in Idaho.

3. Bruton and Joint Trials

Bruton v. United States protects defendants tried jointly when one co‑defendant’s confession incriminates another. If:

• a co‑defendant’s out‑of‑court statement explicitly implicates the defendant;
• the co‑defendant does not testify (so cannot be cross‑examined); and
• the statement is introduced against the defendant;

then there is a Confrontation Clause problem, even with a jury instruction telling jurors to consider the confession only against the speaker. Remedies include:

• Severing trials;
• Redacting co‑defendant statements to remove reference to the defendant; or
• Not admitting the statements at a joint trial at all.

4. Adoptive Admissions

An “adoptive admission” occurs when a person hears another’s statement and, by words or conduct, indicates agreement or acceptance. In law:

• If circumstances are such that an innocent person would naturally deny the statement, but the defendant remains silent or responds in a way that shows assent, the law may treat the statement as if it were the defendant’s own.
• Once a statement is an adoptive admission, it can be used substantively against the defendant and is not hearsay.
• Because it is treated as the defendant’s own statement, it generally does not raise Confrontation Clause problems.

In Horn, the Court held that post‑Miranda silence before a defendant says anything cannot be treated as an adoptive admission, but selective silence after the defendant starts answering questions may sometimes be used, absent a re‑invocation of the right to silence.

5. Harmless Error

Not every constitutional error requires reversal. An error is “harmless” if the appellate court is convinced beyond a reasonable doubt that the error did not contribute to the verdict. The court asks:

• How strong is the properly admitted evidence of guilt?
• How important was the tainted evidence to the prosecution’s case?
• Would a reasonable juror have reached the same conclusion without the improperly admitted material?

In Horn, the Court found the Bruton error harmless because Horn’s own statements and other evidence were more than sufficient to establish guilt.

VI. Impact and Future Implications

A. Fourth Amendment / Probation Searches

State v. Horn establishes a significant rule for Idaho:

The consent given in a probation agreement is sufficient to authorize officers to enter and search the probationer’s residence, even if a co‑tenant who is physically present at the door expressly refuses consent, provided officers confine the search to areas reasonably believed to be under the probationer’s control or shared control.

Practical consequences:

• For law enforcement and probation officers:
  • If they know a resident is on probation with a valid waiver and have reasonable grounds to believe the residence being visited is in fact that probationer’s home, they may enter despite a roommate’s objection, as part of a probation search.
  • They must be prepared to show they reasonably believed particular rooms/containers were under the probationer’s control or shared control.
• For co‑occupants of probationers:
  • They cannot categorically bar probation searches by objecting at the door.
  • If they wish to protect certain items or areas, they must maintain them as clearly private and not shared or under the probationer’s control (e.g., separate locked room, personal safe).
• For defense counsel:
  • Challenges to probation searches will likely focus less on the right to object at the door and more on the scope of the search: Was the room truly shared? Was a particular container clearly exclusive to the non‑probationer? Did officers reasonably believe the probationer had control?
  • Future cases may test the outer bounds—e.g., what counts as a “residence,” how much evidence of residency is needed, and how far shared spaces extend.

The Court did not decide whether Idaho will ultimately harmonize its probation‑search jurisprudence with the federal totality‑of‑circumstances model because that argument was unpreserved. That remains an open question and a potential avenue for future development.

B. Sixth Amendment / Joint Trials and Recorded Confessions

On the confrontation front, Horn sends several messages:

• Warning against casual use of co‑defendant statements: Even when co‑defendants speak jointly to police and both are Mirandized, one defendant’s statement that clearly implicates both (“we were using”) cannot simply be played to the jury against the other, absent adoption or some recognized exception.
• Limits of adoptive admissions post‑Miranda:
  • Post‑Miranda silence, before any waiver by speaking, cannot serve as an adoptive admission.
  • Once a defendant chooses to speak, however, selective silence may lose Doyle protection unless the right is expressly reasserted—thereby potentially opening the door to adoptive‑admission arguments.
• Practical trial management: Prosecutors seeking to admit such recordings in joint trials must:
  • Either redact or avoid using the portions where one co‑defendant incriminates the other; or
  • Risk severance or exclusion of the recorded statement under Bruton.

Defense counsel will likely cite Horn in future motions to sever or to exclude co‑defendant statements, especially recorded statements that are not easily redactable without destroying context.

C. State Constitutional Law and Future Challenges

The Court limited its analysis to the federal Constitution, explicitly noting that Horn did not argue that Article I, section 17 of the Idaho Constitution provides greater protection than the Fourth Amendment. That preserves space for future litigants to argue that Idaho’s constitutional protections should go further than federal law—for example, by:

• Imposing greater limits on probation searches in homes shared with non‑probationers; or
• Modifying the Randolph analysis under state law, even if federal law does not compel such an extension.

For now, however, Idaho law on this issue tracks a relatively officer‑friendly approach, constrained primarily by the requirement that searches be limited to areas under the probationer’s control or shared control.

VII. Conclusion

State v. Horn is a consequential decision at the intersection of Fourth and Sixth Amendment doctrine in Idaho.

On the Fourth Amendment side, the Court draws a bright line: a probationer’s valid Fourth Amendment waiver authorizing searches of his residence is not nullified by a co‑occupant’s contemporaneous objection at the door. Co‑tenants who reside with probationers assume a reduced expectation of privacy in shared areas and cannot use Georgia v. Randolph to block probation searches. At the same time, the Court reaffirms that searches must be reasonably confined to areas under the probationer’s control or joint control, preserving some protection for non‑probationers’ truly private spaces.

On the Sixth Amendment side, the Court fortifies Bruton protections by rejecting the notion that post‑Miranda silence, prior to any waiver by speaking, can serve as an adoptive admission of a co‑defendant’s incriminating statement. Nonetheless, it illustrates how robust harmless‑error review can salvage convictions where independent evidence, particularly the defendant’s own statements, overwhelmingly supports guilt.

Collectively, Horn clarifies the rules governing probation‑home searches in Idaho, underscores the practical consequences of choosing to live with a probationer, and sharpens the evidentiary and constitutional boundaries for admitting co‑defendant statements in joint criminal trials.