Client Advisory

Second Circuit Lowers Bar for Railroad Whistleblower Claims (Ziparo v. CSX Transportation)

November 2025

The Second Circuit in Ziparo v. CSX Transportation revived a retaliation lawsuit under the FRSA, finding that the trial court should have applied the lenient “contributing-factor” causation standard that the Supreme Court applied in Murray v. UBS Securities, a retaliation suit arising under the Sarbanes-Oxley Act. Appellant Ziparo alleged that CSX supervisors asked him to falsify records, and that after he reported it, he was subjected to retaliatory threats and mistreatment. He was fired approximately a month later, after he made a mistake that led to property damage and could have led to a catastrophic derailment or collision. The trial court granted summary judgment to CSX, in part because Ziparo had failed to demonstrate a causal connection between his reporting and his termination.

The Second Circuit reversed, explaining that the FRSA causation standard required Ziparo to meet only a “contributing-factor causation standard,” meaning that the protective activity must be a factor that alone, or in combination with other factors, contributed to CSX’s adverse actions against him. It explicitly overruled several of its related conclusions in Tompkins v. Metro-North Commuter Railroad, 983 F.3d 74 (2d Cir. 2020), explaining that the Supreme Court’s reasoning in Murray required the Second Circuit to adopt the Murray causation standard. Specifically, FRSA plaintiffs no longer need to demonstrate an employer’s retaliatory motive, intent, or animus. Instead, they need only demonstrate that their protected activity “contributed” to the employer’s adverse employment action, including by circumstantial evidence such as sufficiently close temporal proximity.