Late last year, members quietly changed House rules to allow lawmakers to be reimbursed for the cost of lodging, food and other items while on official business in Washington.
Representative Zoe Lofgren, Democrat of California and the chairwoman of the Administration Committee, raised questions in a lengthy letter to J. Thomas Manger, the Capitol Police chief.
The perception that lawmakers are cashing in on their offices has fueled cynicism among voters. Some politicians want to take the current limits further.