State v. Bonacker, 2013 SD 3

April 3, 2010, trooper stops Bonacker for alleged failure to dim headlights; Bonacker, passenger, and headlights demonstration occur; license shows revoked; Bonacker arrest for driving with revoked license.
Bonacker challenged suppression arguing stop should have ended after headlight issue dissipated; magistrate court denied suppression; circuit court affirmed.
Stop justified at inception due to alleged headlight violation under SDCL 32-17-7; issue is whether continued detention and license demand were reasonably related in scope.
Court holds the detention remained within scope of the stop; the officer’s further investigation was justified by ongoing reasonable suspicion after Bonacker admitted no license.
Key legal standard: lawful stop may evolve into longer investigation if based on reasonable suspicion and not unduly prolonging the stop; objective surface of the facts determines reasonableness.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether the detention violated the Fourth Amendment when no violation remained.	Bonacker contends detention exceeded permissible scope after dissipating suspicion.	Bonacker argues continued detention was necessary to verify license status.	No Fourth Amendment violation; detention within scope and reasonable under circumstances.

State v. Overbey, 790 N.W.2d 35 (S.D. 2010) (suppression standards and de novo review.)
State v. Littlebrave, 776 N.W.2d 89 (S.D. 2009) (two-part Terry inquiry; scope of investigation.)
State v. Hayen, 751 N.W.2d 306 (S.D. 2008) (investigative detention limits; duration and scope.)
United States v. Roberts, 687 F.3d 1096 (8th Cir. 2012) (post-stop routine tasks may follow traffic stop.)
Brigham, 382 F.3d 500 (5th Cir. 2004) (scope of investigation at traffic stop.)