State of Iowa v. Gabriel Earl Olson, 15-2197

Shortly after midnight at Springwood State Park, a DNR officer observed Gabriel Olson make a wide right turn entering the campground, crossing into the oncoming lane. The park was closed after 10:30 p.m.
The officer signaled Olson to stop to verify campground registration; Olson said he and his passengers were registered campers.
While speaking with Olson, the officer detected the smell of alcohol, observed watery eyes and slurred speech, and saw a beer can in the cup holder.
Olson admitted drinking, performed field sobriety tests, and registered a .234 BAC on a breath test.
Olson was charged with OWI (first offense) and moved to suppress evidence, arguing the initial stop lacked probable cause or reasonable suspicion; the district court denied suppression (citing community caretaker rationale) and Olson appealed.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether the initial stop of Olson’s vehicle violated the Fourth Amendment / Iowa Constitution	State: Officer had probable cause to stop because he observed a traffic violation (wide turn entering oncoming lane).	Olson: Stop lacked probable cause or reasonable suspicion; therefore seizure was unconstitutional and evidence should be suppressed.	Court: Stop was justified — probable cause existed based on observed traffic violations, so suppression was denied and conviction affirmed.

State v. Lane, 726 N.W.2d 371 (Iowa 2007) (standard of review for suppression rulings and deference to district court factfinding)
State v. Turner, 630 N.W.2d 601 (Iowa 2001) (totality-of-circumstances review for search and seizure)
State v. Pals, 805 N.W.2d 767 (Iowa 2011) (officer needs probable cause for traffic stop or reasonable suspicion for criminal activity)
State v. Tague, 676 N.W.2d 197 (Iowa 2004) (probable cause measured objectively; motivation of officer not dispositive)
State v. Predka, 555 N.W.2d 202 (Iowa 1996) (probable cause for stops when officer observes traffic violations)
State v. Tyler, 830 N.W.2d 288 (Iowa 2013) (Iowa Constitution search-and-seizure analysis and relation to federal standards)