Mechanical Engineering Expert is Qualified Despite His Lack of Familiarity with Gaming Machines

Posted on May 16, 2025 by Expert Witness Profiler

Plaintiff Mark Sabti, a Slot Technician at Greektown Casino, brought this products liability action against Interblock USA, the manufacturer of the Universal Cabinet Craps machine. Sabti alleged design defects and a breach of implied warranty of fitness by the Defendant after the machine’s gas springs failed. The hood of the machine fell and injured his back.

Dr. Stephen Batzer prepared a Rule 26 Report opining that Defendant should have utilized a prop rod or self-locking gas springs, which are used on other gaming machines to hold the hood in place in its elevated position.

However, Defendant filed a motion to strike Plaintiff’s expert Batzer contending he has no experience in the design of casino games or machines utilizing gas springs.

Mechanical Engineering Expert Witness

Stephen Batzer has a Ph.D. in Mechanical Engineering. He is a board-certified forensic engineer and has worked as a forensic engineer. He holds three safety patents and is a member of the American Society of Mechanical Engineers and the Society of Automotive Engineers.

Get the full story on challenges to Stephen Batzer’s expert opinions and testimony with an in-depth Challenge Study.  

Discussion by the Court

Batzer is expected to testify, consistent with his report, that Defendant was negligent in its design of the subject machine and that the subject machine is not fit for its intended use. He also identified alternative means that should have been utilized by the Defendant to prevent uncontrolled descent of the hood of the machine after it had been opened.

To begin with, Batzer relied on the testimony of fellow slot technician James Thiellesen, who testified that other gaming machine manufacturers utilize self-locking gas spring which would prevent the uncontrolled descent of the hood.

Moreover, Sean Matson, Slot Technician Manager at Greektown Casino, also testified that both Aristocrat and Light & Wonder gaming machines use prop rods or hinges that hold the hood in place so that it does not come down uncontrollably.

The Court rejected Defendant’s argument that Batzer is not qualified because he has no experience working on casino gaming machines. Nor was the Court persuaded that Batzer’s opinion was unreliable because he did not perform any scientific analysis or testing.

Held

The Court denied the Defendant’s motion to exclude the testimony of Stephen Batzer.

Key Takeaway:

The Court upheld the admissibility of Stephen Batzer’s expert testimony despite his lack of direct experience with casino gaming machines. These issues also go to the weight to be accorded Batzer’s testimony, not to its admissibility. After all, he has specialized in forensic engineering and safety analysis for twenty years.

Case Details:

Case Caption:Sabti v. Interblock USA A K A Interblock Luxury Gaming Prods., LLC
Docket Number:23cv12620
Court Name:United States District Court for the Eastern District of Michigan, Southern Division
Order Date:May 15, 2025