## Facts

- Carlos Osorio, a construction worker for a hardwood-flooring contractor, used a Ryobi Model BTS15 benchtop table saw at a jobsite.
- The BTS15 was a low-cost, portable benchtop saw purchased from a retailer for about $179.
- While Osorio was making a rip cut, his left hand contacted the spinning blade, causing severe injury.
- Osorio sued the manufacturer entities (collectively, Ryobi) for negligent design and breach of the implied warranty of merchantability under Massachusetts law.
- Osorio’s design-defect theory was that the saw should have incorporated flesh-sensing blade-brake technology (“SawStop”), developed in 1999 and shown to major manufacturers, including Ryobi, around 2000.
- Osorio’s evidence indicated SawStop could detect flesh contact, stop the blade rapidly, and retract it to reduce injury severity.
- Ryobi disputed feasibility for a low-end portable saw, stressing that SawStop would substantially increase price and weight and reduce portability.
- After an eight-day trial, a jury found for Osorio and awarded $1.5 million in damages.
- The district court denied Ryobi’s post-trial motions for judgment as a matter of law (JMOL) and, alternatively, a new trial.

## Issues

1. Whether the evidence permitted a reasonable jury to find the BTS15 defectively designed under Massachusetts design-defect/implied-warranty standards, making denial of JMOL proper.
2. Whether conduct and argument by Osorio’s trial counsel so prejudiced Ryobi that a new trial was required.
3. Whether challenged evidentiary and trial-management rulings were an abuse of discretion warranting a new trial.

## Decision

- The First Circuit affirmed the judgment for Osorio and affirmed denial of JMOL.
- The court held the evidence allowed a finding that a feasible alternative design existed and that omitting it could render the product unreasonably dangerous under Massachusetts law.
- The court held cost and weight impacts did not defeat defect as a matter of law; the jury could weigh those factors against the risk and severity of harm.
- The court rejected the request for a new trial based on attorney misconduct, finding no prejudice requiring reversal.
- The court upheld the challenged evidentiary rulings, finding no abuse of discretion and no unfair prejudice requiring a new trial.

## Legal Principles

- Under Massachusetts law, design-defect claims framed as negligence and implied warranty substantially overlap; the focus is whether the product was reasonably safe for foreseeable uses.
- A plaintiff may prove design defect by showing a reasonable alternative design and that the omission made the product unreasonably dangerous.
- Risk-utility considerations—such as cost, effect on product characteristics, and the probability and severity of harm—are typically for the jury, not resolved as a matter of law on JMOL.
- Evidence bearing on feasibility of an alternative design and the manufacturer’s knowledge of available safety technology is generally relevant, subject to the trial court’s discretion under prejudice and reliability limits.
- New-trial relief based on attorney conduct or evidentiary rulings requires a showing of prejudicial error; appellate review is deferential to the trial judge’s management of the trial.

## Conclusion

The First Circuit allowed a jury to find a low-cost portable table saw defectively designed for lacking known flesh-sensing safety technology, holding that disputes over feasibility, cost, and utility were for the jury and that the district court committed no reversible trial errors in denying JMOL and a new trial.


Osorio v. One World Techs., Inc., 659 F.3d 81 (1st Cir. 2011)