Yellen is likely to face sharp questions from a House committee Wednesday over whether federal banking regulators fell down on the job by not detecting practices at Wells Fargo that allegedly had the nation's second largest bank opening millions of accounts without customers' permission. A group of Democratic senators asked the department to see whether tellers, branch managers and customer service reps were harassed and threatened with termination unless they met sales goals for pushing bank products such as new credit cards. In testimony last week before the Senate Banking Committee, Wells Fargo CEO John Stumpf apologized for the misconduct and promised assistance to affected customers.