Fighting allegations that it improperly maximized its customers’ overdraft fees, Wells Fargo produced trial witnesses to say the bank wasn’t purely motivated by profit.

But U.S. District Judge William Alsup wanted more. During closing arguments Friday in a high-dollar class action, Alsup asked much tougher questions of Covington & Burling partner Sonya Winner, who represents the bank, than of class counsel Richard Heimann from Lieff Cabraser Heimann & Bernstein.