Investigation into Waters alleged wrongdoing may cost taxpayers $1.3 million

Washington (CNN) -- Members of the House Ethics Committee have voted unanimously to spend up to $500,000 extending the contract of a special counsel examining alleged wrongdoing by

California Rep. Maxine Waters, according to a committee statement released Thursday.

Prominent Washington attorney Billy Martin was hired to take charge of the roughly three-year investigation last summer, at a cost of up to $800,000, in order to investigate reports of possible improper communication between committee attorneys and lawmakers on the ethics panel. His contract has been extended twice and runs through the end of the current Congress.

"Mr. Martin will continue to work closely with the Committee as it attempts to complete this matter," the statement said. "We are fully committed to resolving this matter as early in the remainder of this Congress as is possible to do in a thorough, fair and deliberate manner."

Waters is facing accusations that she improperly sought federal assistance in 2008 for OneUnited Bank, a minority-owned bank in which her husband held a financial interest. The bank received $12 million in bailout funds. (Continues)