SAN FRANCISCO — A partner at Davis Polk & Wardwell hired to suss out corruption claims made by Bio-Rad Laboratories Inc.’s former general counsel said in testimony Thursday that the claims were “meritless.”

Martine Beamon.

Martine Beamon, who was retained by Bio-Rad’s independent audit committee in February 2013, also described Bio-Rad’s ousted GC, Sanford Wadler, as evasive and difficult to work with, saying he avoided direct questions, talked in circles and failed to present hard evidence to back up suspicions that the company had engaged in transactions in China that violated the Foreign Corrupt Practices Act.