Background
Mt. Olympus Enterprises, Inc. operates a water and theme park in Wisconsin Dells that includes the Hades 360 roller coaster — a wood-and-steel ride capable of reaching 70 miles per hour, featuring a 140-foot drop and a 360-degree barrel roll. The ride is operated by two attendants who check lap bars and seat belts before dispatch, and it is inspected each morning with a 90-minute inspection protocol, including a weighted-dummy test run. An engineering firm conducted performance testing in 2017 and again in July 2019 — one month before the incident — and concluded Hades was operating within normal industry standards.
On August 25, 2019, Tajudeen Lasisi rode Hades with his daughter. Lasisi had a prior history of chronic back problems and passed posted signage warning guests with neck or back problems not to ride. Lasisi alleges that during the ride Hades made several abrupt stops, with the most severe occurring mid-ride — including potentially while the train was inverted — causing head and neck injury. He did not report any problem to park staff until several days later, and after the ride he spent another hour at the park, had dinner, and drove home before seeking medical attention days afterward.
In August 2022, Lasisi sued Mt. Olympus asserting common law negligence and a violation of Wisconsin’s safe place statute, Wis. Stat. § 101.11. Following discovery, Mt. Olympus moved for summary judgment supported by expert opinion from a mechanical engineer, maintenance and inspection logs, and affidavits from the park’s maintenance supervisor and safety director. Lasisi opposed the motion relying solely on his deposition testimony. The Sauk County Circuit Court (Judge Michael P. Screnock) granted summary judgment to Mt. Olympus and dismissed the complaint with prejudice. Lasisi appealed, also challenging the denial of a reconsideration motion he had supported with a late-submitted affidavit from his daughter.
The Court’s Holding
The Court of Appeals affirmed in a per curiam opinion. On the core summary judgment question, the court held that Lasisi failed to carry his burden at the third step of Wisconsin’s summary judgment methodology — he neither presented sufficient facts to rebut Mt. Olympus’s substantial evidence that Hades was operating normally and within industry standards, nor developed a legal argument showing how the facts he alleged supported a breach of duty or a safe place statute violation. The court emphasized that speculation and unsubstantiated conjecture — such as Lasisi’s hypothesis that an attendant accidentally activated an emergency brake or that a mechanical malfunction occurred — cannot defeat a properly supported summary judgment motion.
The court further held that Lasisi conceded Mt. Olympus’s argument that expert testimony would be required to support a ride-malfunction theory, because he failed to address that argument in his reply brief. Similarly, the court deemed conceded Mt. Olympus’s argument that res ipsa loquitur was inapplicable, as Lasisi raised no such argument on appeal. The court also affirmed the denial of the reconsideration motion, finding Lasisi had abandoned that issue by failing to develop any argument on appeal regarding the circuit court’s discretionary denial.
On the safe place statute claim, the court noted that the inquiry focuses on the condition of the property rather than a negligent act, but concluded Lasisi likewise failed to identify any unsafe structural or equipment condition that caused his injury. His undeveloped references to a loose lap bar and abrupt stops — without any legal argument connecting those facts to a statutory violation — were insufficient to survive summary judgment.
Key Takeaways
- A plaintiff opposing summary judgment in a premises-liability case cannot rely solely on deposition testimony describing an incident when the defendant has submitted expert reports, inspection logs, and lay affidavits demonstrating proper maintenance and industry-standard operation.
- Speculation about a possible cause of injury — such as an attendant accidentally pressing an emergency stop button or an unidentified mechanical malfunction — does not create a genuine issue of material fact under Wis. Stat. § 802.08.
- Failure to respond to a defendant’s argument that expert testimony is required to establish a technical malfunction claim constitutes a concession of that argument under Wisconsin appellate practice.
- A warning sign at the ride entrance advising guests with back or neck problems not to ride was among the facts the court noted in the undisputed record, underscoring the importance of documented warnings in amusement-ride liability cases.
Why It Matters
This decision reinforces the practical importance of expert testimony in amusement-ride injury litigation. Where a ride operator presents engineering inspections, daily maintenance logs, and expert opinion that its equipment met industry standards, a plaintiff who forgoes expert witnesses and relies on lay testimony alone faces an uphill battle at summary judgment. Plaintiffs’ counsel in similar cases should retain mechanical or safety engineering experts early and ensure those opinions are timely submitted in opposition to dispositive motions.
The opinion also illustrates Wisconsin’s demanding standard for defeating summary judgment: pointing to factual disputes is not enough — the nonmoving party must tie those facts to specific legal elements and show why they are material. The court’s willingness to treat multiple unbriefed arguments as conceded serves as a reminder that appellate advocacy requires fully developed legal arguments at every stage, not merely a recitation of disputed facts.