State v. Robert Joseph Stietz, 2017 WI 58

Stietz, a 64-year-old farmer, patrolled private land surrounded by fenced private property with posted no-trespassing signs and an easement; wardens entered this private land to investigate suspected hunting after hours.
Wardens Frost and Webster approached Stietz on his land, identified him, and requested to see his rifle, which he initially refused to surrender; a struggle ensued over the rifle.
During the struggle the rifle was wrested from Stietz; both wardens drew handguns and a standoff ensued with all three parties armed.
Stietz testified he believed the wardens were trespassers and feared for his safety, while wardens testified they identified themselves as wardens and sought to disarm him for safety.
The circuit court refused Stietz’s requests for self-defense and trespass jury instructions, prompting postconviction appeals and this review.
Wisconsin courts ultimately concluded there was sufficient basis to instruct on self-defense and trespass, and remanded for trial, noting Fourth Amendment concerns about the wardens’ private-land entry.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether the circuit court properly refused self-defense instruction	Stietz asserted evidence supported self-defense; wardens were accused of trespass and unlawful entry.	State contends self-defense lacked reasonable belief given wardens wore orange and identified themselves; otherwise no basis for instruction.	Self-defense instruction warranted; circuit court erred in refusing.
Whether the circuit court erred by not instructing on trespass	Wardens trespassed on private property; trespass evidence supported jury instruction.	Wardens had statutory authority to enter; no trespass, so no trespass instruction needed.	Trespass instruction should be given on remand.
Whether the circuit court's error was harmless or affected substantial rights	Self-defense and trespass instructions could have altered the verdict on some counts.	Any error was harmless; jury acquittals on others show no prejudice.	Error affected substantial rights; not harmless.
Whether wardens’ private-land entry violated Fourth Amendment protections	Wardens lacked authorization to enter fenced private land without consent or warrant.	Wardens acted under open fields/departmental authority; entry was justified for enforcement.	Wardens violated Fourth Amendment rights by entering private land without lawful authority; remand advised.

State v. Head, 255 Wis. 2d 194 (2002 WI 99) (establishes the standard for determining sufficiency for self-defense jury instructions)
State v. Coleman, 206 Wis. 2d 199 (1996) (circuit court's discretion to give jury instructions and informing the jury of the law)
State v. Mendoza, 80 Wis. 2d 122 (1977) (reasonableness determined from the accused's standpoint at the time)
State v. Peters, 258 Wis. 2d 148 (2002 WI App 243) (low 'some evidence' threshold for self-defense in jury instructions)
Maichle v. Jonovic, 69 Wis. 2d 622 (1975) (reasonableness of beliefs is a jury question)