The bribery case against Rep. William Jefferson, D-La., highlights, yet again, the failure of Congress to police its own members in any meaningful way.

The Justice Department has finally indicted Jefferson for allegedly soliciting hundreds of thousands of dollars in bribes from various companies, often for projects intended for Africa. He is accused of using his former seat on the House Ways and Means Committee, which oversees trade, to promote the firms' projects without disclosing his financial interests in them.

Jefferson should spare his constituents further embarrassment by resigning. Federal agents who raided his Washington home found $90,000 in cash in his freezer, part of a payment from an informant in the probe. Two of his associates, including a former congressional staffer, have pleaded guilty and agreed to testify against Jefferson.

The congressman says he's not guilty. And of course, there is a presumption of innocence in this country. But if that ship hasn't sailed in Jefferson's case, certainly it has been untied from the dock.

Congress does not expel members prior to conviction, but that doesn't preclude an indicted lawmaker from quitting.

House Democratic leaders have already stripped Jefferson of his last committee assignment; Republicans wisely blocked an earlier effort to give Jefferson a seat on the Homeland Security Committee.

If convicted, Jefferson would join former Reps. Randy "Duke" Cunningham, R-Calif., and Bob Ney, R-Ohio, as the most recent examples of corrupt lawmakers serving jail time. And what did Congress do in each of these cases? Nothing, really.

The House Ethics Committee did start an investigation of Jefferson last year, long after the raid on the congressman's home. But the panel hadn't taken any action when the 109th Congress ended, and the new Democratic-controlled House had not reauthorized a probe by the time Jefferson was indicted. After the indictment, the House swiftly approved a new ethics investigation against him.

When Republicans ruled Congress, Democrats decried the "culture of corruption" and vowed to drain the swamp. The new Democratic majority did impose a ban on gifts from lobbyists. And last month the House approved an ethics bill that would require lobbyists to disclose their efforts to "bundle" large campaign contributions on behalf of lawmakers. It's expected that the House and Senate will agree on final ethics legislation before the August recess.

But the most important enforcement proposal languishes. The move to create an independent office to investigate ethics complaints has been shunted aside by House Speaker Nancy Pelosi, D-Calif., to a task force that is studying the idea. In Washington, "task force" is usually code for killing a popular proposal slowly and quietly.

If Democratic leaders are serious about making good on their promise, they should press ahead with the proposal for an independent office to investigate ethics complaints. The House Ethics Committee has demonstrated many times in recent years that lawmakers are simply incapable of sanctioning themselves.