On January 10, 2025, Plaintiffs filed their First Amended Complaint against Defendant, alleging they suffered injuries when a wholly unprovoked group of highly intoxicated passengers (“the Aden Family”) physically assaulted and battered them while attending a “White Party” on the Defendant’s Vessel. The Plaintiffs, other than Daniella Dos Santos Vieira (“Plaintiff”), settled their claims with Defendant. As a result, the First Amended Complaint’s three remaining claims are: general negligence (Count I), negligent failure to warn (Count V), and premises liability (Count IX).
Defendant sought to strike the proposed testimony of Plaintiff’s expert, Ronald J. Thomason.

Maritime Expert Witness
Ronald J. Thomason has over 25 years of experience in providing security assessment, planning, and training services to commercial maritime industry, government, and law enforcement personnel responsible for oversight and enforcement of regulatory compliance of security standards and practices.
Discussion by the Court
In preparing his report, Thomason reviewed the Cruise Vessel Security and Safety Act of 2010 (“CVSSA”), the International Ship and Port Facility Security (ISPS) Code, as well as various case documents.
First, Thomason opined that Defendant did not have enough security staff dedicated to provide a presence for deterrence and appropriate response at the “White Party”. Second, Thomason opined that Defendant did not comply with the requirements of the CVSSA. Third, Thomason opined that the Plaintiffs acted reasonably in response to a foreseeable and preventable unprovoked attack. Fourth, Thomason opined that Defendant failed to follow its own published policy, and the “White Party” bar staff failed to follow the established procedures for identifying inebriated guests, terminating their consumption of alcohol, and notifying security of their possible threat to the safety and enjoyment of other event attendees. Fifth, Thomason opined that had Defendant complied with the requirements of the CVSSA, this incident could have been detected and deterred before escalating into a physical assault.
I. Methodology and Helpfulness
First Opinion
First, Thomason opined that based on his years of training, education, and experience Defendant did not have enough security staff present for deterrence. He opined that all of Defendant’s security staff are required to be trained in the CVSSA, which provides specific instruction on the detection, prevention, evidence collection, and reporting of specific criminal threats.
However, the Court found that Thomason’s opinion improperly relied upon regulations that are inapplicable based on the facts of this case.
As to Thomason’s suggestion that more security would have prevented the altercation, Thomason did not explain how additional security would have prevented the sudden punch in this case. To the contrary, the CCTV camera shows at least two employees in the vicinity of Plaintiff and her assailant at the time of the punch.
Second Opinion
Thomason’s second opinion is that Defendant failed to comply with the requirements of the CVSSA. As the Court previously determined, the CVSSA is not implicated because the incident does not involve a homicide, kidnapping, sexual assault, suspicious death, theft of money over $10,000, or a physical assault with serious bodily injury.
Third Opinion
Thomason’s third opinion is that, based on his experience, Plaintiff acted reasonably in response to a foreseeable and preventable unprovoked physical attack. Thomason’s opinion relied only on his experience. Moreover, his opinion did not explain how his experience led to that conclusion, why his experience is a sufficient basis for the “reasonable” actions of the Plaintiff or the “foreseeability” of the assault.
Fourth Opinion
Thomason’s fourth opinion argued Defendant failed to follow its own published policy. However, Thomason failed to articulate what these established procedures are, how the bar staff failed to follow them, or how the unreferenced procedures would have prevented the sudden punch thrown at Plaintiff.
Fifth Opinion
Fifth, Thomason opined that had Defendant complied with the CVSSA and Defendant’s published policies for dealing with the intoxicated guests, this incident would have been detected and deterred prior to ever escalating into a fight. However, this summation of Thomason’s prior opinions is entirely speculative and not rooted in a methodology that relies on anything other than his experience.
The Court found that Thomason’s analysis lacked a reliable methodology and would not be helpful.
Held
The Court granted Defendant’s Daubert motion to strike the testimony of Ronald J. Thomason.
Key Takeaway
The trial court’s gatekeeping function requires more than simply taking the expert’s word for it. Moreover, Thomason’s first opinion pivots from security measures to the suggestion that the ship staff was improperly trained on how to detect intoxicated guests. Thomason provided no support for this assertion either in his experience or an applicable regulation.
Case Details:
| Case Caption: | Vieira v. MSC Cruises S.A. |
| Docket Number: | 1:24cv24991 |
| Court Name: | United States District Court, Florida Southern |
| Order Date: | July 15, 2026 |
Leave a Reply