Democrat Sen. Ron Wyden and Republican Sen. Bill Cassidy clashed over pre-existing condition protections in Cassidy’s Obamacare overhaul bill, drawing a sharp rebuke from the panel’s chairman.

Cassidy, of Louisiana, was taking the unusual step of answering questions before the Senate Finance Committee during a hearing Monday on his Obamacare overhaul bill. Experts say a new version of the bill makes it easier for insurers to charge sick people more money.