Reading through the addendum to Sen. Bob Corker’s financial disclosure, you might think the Tennessee Republican had been seriously misreporting assets and income.

But the reality might more underscore the shortfalls of the system.

When Roll Call calculates the 50 richest members of Congress each year, the minimum net worth figures are based on the asset and liability sections of their financial disclosures, which allow for broad ranges for values that often do not give a precise representation, especially for the holdings of wealthier members.

The amendment the Tennessee Republican filed on Dec. 11 would not change his position on the current list, where he ranks 23rd. But it does change his minimum net worth.

“I am extremely disappointed in the filing errors that were made in earlier financial disclosure reports, and after completing a full, third-party review, we have corrected this oversight,” Corker said in a statement.

David Hawkings’ Whiteboard: Wealth of Congress

But for some government watchdog groups, this incident raises questions about what led to the discrepancies on Corker’s reports in the first place, and points to broader problems within the disclosure and congressional ethics process.

In 2007, Ken Boehm, chairman of the National Legal and Policy Center, co-wrote a letter to congressional leaders calling for changes to the financial disclosure process, including narrowing or eliminating the form’s value ranges.

“It’s important to know how much it was because that describes how big the possible offense was,” said Boehm, pointing to the broad ranges for both assets and incomes used in the current disclosure process.

Groups can call for new rules, Boehm said, but that won’t make a difference unless the Ethics Committee enforces them.

“If these ethics rules pertaining to financial disclosure reports are not enforced by the House and Senate Ethics Committees, respectively, then I still think you’re going to end up with a very weak record in terms of members of Congress who are inclined to break the rules,” Boehm said.

Corker’s new disclosure revises upward the value of the Corker Development Corporation, an umbrella for the senator’s longtime real estate investments, from a range of $1,001 to $15,000 to a range of $500,001 to $1 million. But there are some countervailing reductions elsewhere in the documentation.

Corker retained a third-party accountant to review his financial disclosures for his entire Senate tenure after The Wall Street Journal began questioning the senator’s reporting of income, particularly in hedge funds, going beyond what might have been required to clean up the original discrepancies.

The Journal also pointed to apparent discrepancies in reporting income from investments.

In the financial disclosure report amendments, Corker said the discrepancies resulted from mistakes by an accounting firm that was putting together the reports.

But Boehm said ultimately the member is responsible.

“The rule is if you sign one of those forms, you take responsibility for the correctness or lack of correctness,” he said.

“One has to wonder, how did Corker make such a grave mistake?” asked Craig Holman, a lobbyist with Public Citizen who helped draft the the 2007 Honest Leadership and Open Government Act. “I understand minor reporting problems but we’re talking millions and millions of dollars from questionable sources.”

Holman said the Corker incident also demonstrates that the Senate Ethics Committee does not closely examine financial reports, and just gives them a “rubber stamp.”

“It shows that the Ethics Committee isn’t stepping up to the plate in ensuring that the disclosures are accurate and full,” Holman said. “Had it not been for The Wall Street Journal doing its own independent investigation, we’d still be left with inaccurate records from Corker.”

Holman called for an office similar to the House’s “Office of Congressional Ethics,” which is not made up of lawmakers, and, he argued, can operate more independently. The Senate does not have a similar office.

Holman said members of Congress are less inclined to police themselves, so they need an independent body to step in.

A spokeswoman for Ethics Chairman Johnny Isakson, R-Ga., referred Roll Call to the Ethics Committee, which did not respond to a request for information about the Corker case.

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