Democrats in Congress have called on Republican presidential candidate Mitt Romney to release more tax returns, but most of them have refused to release their own tax forms.

For three months, McClatchy requested the most recent tax returns from all 535 members of Congress, but only 13 Democrats and 3 Republicans shared their detailed tax information. The rest either refused to share their tax returns or ignored McClatchy's request.

Members of Congress are required to file financial disclosure reports that list their major sources of earned and unearned income. However, the disclosure reports do not contain the same detail of information found in tax returns, omitting financial data such as spousal income.

Romney has repeatedly insisted that he would not release more than his 2010 and 2011 tax returns, even though his own father set a standard of releasing 12 years of returns.

"In the political environment that exists today, the opposition research of the Obama campaign is looking for anything they can use to distract from the failure of the president to reignite our economy," Romney told the conservative National Review Online.

"I'm simply not enthusiastic about giving them hundreds or thousands of more pages to pick through, distort and lie about," he added.

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