State v. Swartz, 517 S.W.3d 40

Background

On March 21, 2014 Sergeant Nicholas Berry observed Jerry J. Swartz driving partly in the center of two separate two-way roads, failing to fully stop at a stop sign, and later stopped him; a patrol-car video was shown at trial.
After stopping Swartz, Berry detected odor of alcohol, observed glassy/bloodshot eyes and slurred/mumbled speech, and noted difficulty handling documents; Swartz refused a portable breath test and was arrested.
A search warrant was obtained for two blood draws at a hospital (1:36 a.m. and 2:06 a.m.); lab results showed BACs of 0.107% and 0.096%.
Swartz was convicted by a jury of Driving While Intoxicated (DWI) and Failure to Drive on the Right Half of the Roadway (Count II); sentence: six months (suspended) and two years’ probation for DWI; $50 fine for Count II.
On appeal Swartz raised six points: (1) warrant did not authorize blood testing, (2) stop lacked justification because road was not "sufficient width," (3) chain-of-custody gap for blood evidence, (4) special prosecutor lacked authority/oath, (5) lack of probable cause to arrest for DWI, and (6) instructional error for Count II omitting "sufficient width."
The court affirmed the DWI conviction but reversed Count II (failure to drive on right half of roadway), holding the jury instruction omitted an essential, contested element (roadway "sufficient width").

Issues

Issue	Swartz's Argument	State's Argument	Held
Warrant scope: did warrant for blood draw authorize subsequent testing?	Warrant authorized only seizure (draw); chemical analysis is a separate Fourth Amendment search requiring explicit authorization.	A warrant to seize blood for DWI evidence necessarily authorizes testing confined to the probable-cause purpose.	Test of blood authorized; warrant sufficient. Point One denied.
Validity of stop: did officer have reasonable suspicion given alleged road width issue?	Stop was unlawful because roadway was not "sufficient width" under §304.015, so no basis to stop for that violation.	Independent traffic violation existed: failure to fully stop at a stop sign provided reasonable suspicion for the stop.	Stop was justified on the stop-sign violation alone. Point Two denied.
Chain of custody: did a two-day custody period void admissibility of blood results?	Two-day gap (samples in patrol car then evidence officer custody) broke chain and undermined identity/condition of samples.	Evidence officer signed custody; sealed box received by lab; no evidence of bad faith or tampering—gap goes to weight, not admissibility.	No plain error shown; admission proper. Point Three denied.
Prosecutor authority: was special prosecutor improperly appointed/lacking oath?	Special prosecutor lacked statutory authority/oath and thus could not prosecute.	Court may appoint special prosecutor under §56.110 and inherent authority; no statutory oath requirement for a court-appointed special prosecutor.	No error. Point Four denied.
Probable cause for DWI arrest: were observations sufficient?	Odor, bloodshot eyes, and mumbled speech alone insufficient for probable cause.	Officer observed erratic driving, odor, bloodshot eyes, slurred speech, difficulty handling documents—totality supports probable cause.	Probable cause existed. Point Five denied.
Instructional error on Count II: did jury instruction omit element that roadway be of "sufficient width"?	Instruction omitted required element; court barred Swartz from proving road <30 feet; omission prejudiced defense.	Instruction tracked State's formulation; road width was effectively uncontroverted by State evidence.	Jury instruction omitted an essential, disputed element; prejudice found. Point Six granted—Count II reversed and remanded.

Key Cases Cited

Missouri v. McNeely, 569 U.S. 141 (search warrant generally required for nonconsensual blood draw)
Skinner v. Ry. Labor Executives’ Ass’n, 489 U.S. 602 (1989) (recognized body intrusion and chemical analysis as distinct privacy interests in blood testing)
Schmerber v. California, 384 U.S. 757 (1966) (drawing blood is a search implicating Fourth Amendment)
State v. Pike, 162 S.W.3d 464 (Mo. banc 2005) (standards for reviewing vehicle stops and reasonable suspicion)
State v. Barks, 128 S.W.3d 513 (Mo. banc 2004) (traffic violation observation supports a lawful stop)
State v. Martines, 331 P.3d 105 (Wash. App. 2014) (holding blood draw and testing were separate searches)
State v. Martines, 355 P.3d 1111 (Wash. 2015) (Washington Supreme Court rejecting Martines appellate holding; warrant for draw necessarily authorizes testing)
State v. Pennington, 493 S.W.3d 926 (Mo. App. W.D. 2016) (chain-of-custody/gap affects weight, not admissibility absent bad faith)
State v. Brand, 309 S.W.3d 887 (Mo. App. W.D. 2010) (review standard for suppression rulings)