Date: Jul 1, 2026

Particularized Suspicion to Expand a Traffic Stop into DUI Testing; Waiver of Unpreserved Independent Blood Test Claims

Introduction

In State v. L. Johnson (2026 MT 138N), the Montana Supreme Court reviewed a misdemeanor conviction arising from a late-night traffic stop in Bozeman. Defendant-Appellant Lisa Rene Johnson was stopped after officers reported observing an inoperable headlight and weaving within her lane. The stop expanded into a DUI investigation based on additional observations (odor of alcohol, slurred speech, difficulty producing documents, and an admission of drinking). Johnson ultimately was convicted of Operating a Vehicle with an Alcohol Concentration of 0.08 or More under § 61-8-1002(1)(b), MCA.

The appeal principally tested (1) whether there was particularized suspicion for the initial stop and for expanding the stop into DUI testing, (2) whether the trial court abused its discretion in admitting the DUI-investigation evidence (notably Intoxilyzer 9000 results), and (3) whether an asserted due process right to an independent blood test could be raised for the first time on appeal.

Important procedural note: the Court resolved the case by memorandum opinion under its Internal Operating Rules and expressly stated the decision “shall not be cited and does not serve as precedent.” Nonetheless, the opinion is a useful illustration of how Montana courts apply settled suppression standards to common DUI-stop fact patterns.

Summary of the Opinion

The Court affirmed the denial of Johnson’s suppression motions and upheld the conviction. It concluded:

The initial stop was supported by particularized suspicion under § 46-5-401(1), MCA, based on the observed headlight violation and weaving within the lane.
The officers had particularized suspicion to expand the stop into a DUI investigation and administer standardized field sobriety tests (SFST) and a Preliminary Breath Test (PBT).
Claims that the Municipal Court improperly admitted various items of DUI evidence failed for inadequate briefing/record support; the State did not introduce PBT results at trial; and there was no developed argument showing a foundational defect as to the Intoxilyzer 9000.
The independent blood test/due process theory was unpreserved and therefore waived; the Court declined to address it.

Analysis

Precedents Cited

1) Appellate posture and standards of review

City of Bozeman v. Cantu, 2013 MT 40, ¶ 10, 369 Mont. 81, 296 P.3d 461: The Court emphasized that when a case reaches the Supreme Court after municipal court and then district court review, the Supreme Court reviews it “as if the appeal originally had been filed” in the Supreme Court and examines the record independently. This framing limits the practical significance of the district court’s reasoning and refocuses attention on the municipal court record.
State v. Kenfield, 2009 MT 242, ¶ 15, 351 Mont. 409, 213 P.3d 461: Provided the suppression-review framework: factual findings are reviewed for clear error; legal interpretation/application is reviewed for correctness.
Leichtfuss v. Dabney, 2005 MT 271, ¶ 21, 329 Mont. 129, 122 P.3d 1220: Cited for plenary review of conclusions of law.
State v. Fleming, 2019 MT 237, ¶ 9, 397 Mont. 345, 449 P.3d 1234: Set the abuse-of-discretion standard for evidentiary rulings and later supported the Court’s refusal to entertain certain late-raised “plain error” requests.

2) Particularized suspicion for the traffic stop

State v. Ellison, 2000 MT 288, ¶ 15, 302 Mont. 288, 14 P.3d 456: Supplied the two-part test: (1) objective data and reasonable inferences by an experienced officer; (2) resulting suspicion of wrongdoing.
State v. Pratt, 286 Mont. 156, 161, 951 P.2d 37, 40 (1997): Reinforced the “totality of circumstances” approach, treating particularized suspicion as a fact-intensive question.
State v. Wagner, 2013 MT 159, ¶¶ 11-12, 370 Mont. 381, 303 P.3d 285: (a) The inquiry centers on what the officer knew/observed at the time of the stop, not later defense testimony; (b) a statutory violation alone can justify a stop.
State v. Harning, 2022 MT 61, ¶ 18, 408 Mont. 140, 507 P.3d 145: Clarified that officers need not be certain or correct to have particularized suspicion.
State v. Matthews, 2025 MT 129, ¶ 8, 422 Mont. 392, 571 P.3d 1024: Confirmed that weaving within a lane—though not necessarily a discrete traffic offense—can be an articulable fact supporting suspicion.
Heien v. North Carolina, 574 U.S. 54, 57, 135 S. Ct. 530 (2014): Used to support the proposition that searches/seizures may remain permissible even when the justification includes a reasonable factual mistake.
State v. Deines, 2009 MT 179, ¶ 20, 351 Mont. 1, 208 P.3d 857: Reinforced appellate restraint: the Supreme Court does not reweigh evidence or revisit credibility determinations.

3) Particularized suspicion to expand into DUI investigation and SFST/PBT

State v. Larson, 2010 MT 236, 358 Mont. 156, 243 P.3d 1130: Established (and the Court reiterated) that SFSTs are searches under the United States and Montana constitutions and require particularized suspicion of impairment.
State v. Estes, 2017 MT 226, ¶ 17, 388 Mont. 491, 403 P.3d 1249, and State v. Zietlow, 2017 MT 148, ¶ 9, 388 Mont. 26, 396 P.3d 740: Reaffirmed the Ellison formulation and totality-of-circumstances lens for evaluating suspicion.
State v. Stanley, 2024 MT 271, ¶ 29, 419 Mont. 61, 558 P.3d 1147: Supported the principle that officers may expand the scope of a stop when new information arises during the encounter.
Hulse v. State, 1998 MT 108, ¶ 39, 289 Mont. 1, 961 P.2d 75: Quoted for the idea that particularized suspicion supporting a stop can also support field sobriety testing (depending on facts).
State v. Steinmetz, 1998 MT 114, 288 Mont. 527, ¶¶ 16, 18, 961 P.2d 95: Central to rejecting the “coercion/no-consent” argument: if there is particularized suspicion, SFSTs may be requested/administered; a lawful request is not “coercion” without more; and police need not warn a person of the right to withhold consent.
State v. Olson, 2002 MT 211, ¶ 21, 311 Mont. 270, 55 P.2d 935: Cited for the principle that knowledge of the right to refuse is only one factor in determining whether consent was voluntary (a totality inquiry).

4) Evidentiary and briefing principles

City of Billings v. Peterson, 2004 MT 232, ¶ 45, 322 Mont. 444, 97 P.3d 532: The Court relied on this to decline to develop Johnson’s underexplained evidentiary arguments—underscoring that appellants must do more than cite authority; they must apply it to the record.

5) Issue preservation and waiver on appeal

State v. Homer, 2014 MT 57, ¶ 12, 374 Mont. 157, 321 P.3d 77: Restated the baseline rule that arguments raised for the first time on appeal are generally not considered.
State v. Akers, 2017 MT 311, ¶ 20, 389 Mont. 531, 408 P.3d 142: Applied to emphasize preservation at the first-level appellate court as a prerequisite to Supreme Court review.
State v. Paoni, 2006 MT 26, ¶ 35, 331 Mont. 86, 128 P.3d 1040: Cited for the requirement of a timely objection to preserve an issue for appeal.
State v. Fleming, 2019 MT 237, ¶ 40, 397 Mont. 345, 449 P.3d 1234: Invoked to note the Court’s reluctance to entertain plain error requests raised for the first time in a reply brief.

Legal Reasoning

1) The initial stop: objective observations at the time control

Applying § 46-5-401(1), MCA and the Ellison framework, the Court focused on the contemporaneous facts: both officers testified they saw an inoperable headlight and weaving; the municipal court found the dashcam corroborated those observations. Under Wagner, the legality of the stop turns on what the officer perceived at the moment of seizure, not on Johnson’s later testimony and headlight-repair receipt.

The Court also neutralized Johnson’s “dismissal/acquittal means the stop was unlawful” theory. Because a stop can be justified by a reasonable observation (and even by a reasonable factual mistake under Heien v. North Carolina), the later outcome on a traffic charge does not retroactively erase the officer’s basis at the time of the stop.

Finally, the Court declined to revisit credibility determinations (State v. Deines), effectively deferring to the municipal court’s resolution of conflicting evidence.

2) Expansion to DUI investigation: accumulating indicators under totality of circumstances

The Court treated the DUI expansion as a separate constitutional step requiring its own justification. Citing State v. Larson, it reiterated that SFSTs are searches and require particularized suspicion of impairment. It then credited several indicators that developed by the time the officers asked Johnson to exit: late hour, weaving within the lane, odor of alcohol, slurred speech, difficulty producing documents, and an admission to drinking.

Under State v. Stanley, officers may expand the stop based on new information learned during the encounter. Under State v. Matthews, weaving within the lane is an articulable impairment indicator. The Court concluded these facts, viewed together, supplied sufficient particularized suspicion to proceed with SFSTs and a PBT.

3) “Coercion” and consent arguments: a lawful request is not automatically coercive

Johnson argued she was coerced to exit the vehicle and perform SFSTs. The Court relied primarily on State v. Steinmetz to reject the claim: when an officer has particularized suspicion, requesting SFSTs is lawful and not “coercion” without additional evidence showing the defendant’s will was overborne. It also emphasized Steinmetz’s rule that police need not advise a person of the right to withhold consent. In discussing voluntariness, the Court cited State v. Olson for the totality-of-circumstances approach and treated Johnson’s “okay” response and compliance as consistent with voluntary consent on this record.

4) Evidence-admission challenges: inadequate development and lack of record support

Johnson attacked the admission of DUI-investigation evidence, but the Court found the contentions either irrelevant to what actually happened at trial (the State did not introduce the PBT results) or insufficiently argued. Applying City of Billings v. Peterson, it declined to craft arguments on her behalf regarding refusal evidence, constitutional theories, or foundational challenges to the Intoxilyzer 9000. With no developed explanation of what foundational element was missing or how the evidence was admitted in error, the Court held there was no abuse of discretion.

5) Independent blood test/due process theory: waiver for lack of preservation

Johnson raised for the first time on appeal a due process claim that she was not advised of the right to an independent blood test. The Court applied preservation rules: it generally will not consider new issues (State v. Homer), requires preservation in the first-level appellate court (State v. Akers), and treats failure to object as waiver (State v. Paoni), consistent with § 46-20-104(2), MCA. Because Johnson neither preserved the issue nor sought plain error review, the Court declined to address it.

Impact

Although expressly nonprecedential, the opinion reinforces several practical takeaways likely to shape litigation behavior in Montana DUI cases:

Video corroboration matters: where dashcam/bodycam supports the officer’s observations (e.g., headlight condition, weaving), trial-level credibility findings are difficult to dislodge on appeal.
DUI expansion is analyzed step-by-step: even a valid traffic stop does not automatically justify SFSTs; officers must be able to articulate impairment indicators. Here, odor, slurred speech, document fumbling, admission of drinking, and weaving collectively sufficed.
Defense briefing must connect law to record: generalized citations to statutes and cases, without specifying the precise trial ruling and the missing foundation, risk summary rejection under City of Billings v. Peterson.
Preservation is decisive: independent blood test/due process claims (and similar theories) must be raised in the trial court and properly carried through intermediate appeal stages, or they will be deemed waived.

Complex Concepts Simplified

Particularized suspicion: A common Montana standard for brief investigative stops: specific, objective facts (and reasonable inferences) suggesting a person has committed, is committing, or is about to commit an offense. It is less than probable cause and is judged under the “totality of circumstances.”
Totality of the circumstances: Courts do not isolate each fact; they assess how all facts combine. For example, “weaving,” “odor of alcohol,” and “slurred speech” together can create a stronger inference of impairment than any one fact alone.
SFSTs as “searches”: Under State v. Larson, standardized field sobriety tests are treated as searches, meaning police must have particularized suspicion of impairment before administering them.
PBT vs. Intoxilyzer 9000: A PBT is typically a roadside screening tool used during investigation. The Intoxilyzer 9000 is the evidentiary breath test administered in a controlled setting (here, the detention center) and was the key chemical test supporting the per se BAC conviction.
Preservation / waiver: To raise an issue on appeal, a defendant generally must object or otherwise present the claim in the trial court at the proper time. If not preserved, appellate courts usually treat it as waived and will not decide it.

Conclusion

State v. L. Johnson affirms a familiar Montana DUI suppression framework: officers may initiate a stop when objective observations provide particularized suspicion (including an observed equipment violation and weaving), and may expand the stop to SFSTs and related DUI investigation when additional indicators of impairment emerge during the encounter. The decision also underscores appellate discipline—deference to trial-level credibility findings, insistence on developed legal argument, and strict enforcement of issue-preservation rules, particularly for newly asserted due process theories such as the claimed right to an independent blood test.