Group of Senate Democrats say Trumps continued withholding of his tax returns proves he is ethically compromised and tied to Russian interests

Senate Democrat on Thursday called on Donald Trump to release his tax returns, saying the Republican nominees refusal to do so constituted evidence he was ethically compromised and perhaps unfit to serve as president.

Harry Reid, the Democratic Senate leader who in 2012 famously accused Mitt Romney of not having paid taxes for 10 years, said Trump was misinforming the American people by bucking decades of tradition regarding the release of tax returns by presidential candidates.

And that is a gross understatement, Reid told reporters at a press conference on Capitol Hill. The American people deserve and respect that any leader of the free world be transparent but Trump doesnt do it, because he doesnt respect the office he is seeking or the American people.

Trump has declined to release his tax returns, quoting an audit by the Internal Revenue Service which in fact does not legally mean returns cannot be released.

Last week, his son Donald Trump Jr made a different excuse, saying releasing the documents would distract from presidential candidates message.

Senate Democrats are seeking to force Trumps hand by pushing legislation that would require presidential nominees to release their tax returns.

Republicans blocked the effort on the floor last week, and asked in return that the bill be amended to include a provision that would rescinded security clearances for federal employees who demonstrated extreme carelessness in handling classified information. A including references to Hillary Clintons use of a private email server while secretary of state, it was blocked by Democrats.

Trumps reluctance to make public his tax returns has nonetheless drawn scrutiny from both political parties. Mitch McConnell and Paul Ryan, the Republican leaders in the Senate and the House, have both said Trump should release the returns, pointing to longstanding precedent.

Clinton has released personal tax returns covering 2007 to 2014; her familys tax returns from 2000 to 2006 were made public during her 2008 presidential operate. She and her husband Bill Clintons records dating back to 1977 are now available to the public. Last month, Clinton disclosed her federal income tax return for 2015. Her running mate, Tim Kaine, and his wife Anne Holton released 10 years of their own returns.

Trump, whose running mate, Mike Pence, has released 10 years of tax returns, is the first major-party nominee to withheld his taxation records since Gerald Ford, who presumed the presidency in accordance with the resignation of Richard Nixon in 1974. Ford released a summary of data from eight years of tax returns but never disclosed the complete document. Nixon released his tax returns in 1973 while they were under audit.

Romney has also called upon Trump to release his returns, calling the failure to do so disqualifying. In 2012, Trump exhorted Romney to release his tax returns after the former Massachusetts governor was reluctant to do so. Romney eventually put out limited information on his taxes after the Republican convention.

In their Thursday press conference, Democrats said Trump was afraid of what his returns would reveal about his business practices, charitable giving and ties to foreign governments.

Its likely those tax returns will show major income for Trump and his family from Russia from Russian business interests, from Russian oligarchs, said Chris Murphy, a senator from Connecticut.

It will show that the decisions he will build on whether to turn on or off sanctions against Russia could have a multimillion-dollar impact on his wealth. Thats not embarrassing, thats disqualifying.

Trumps penchant for praising Russias chairperson, Vladimir Putin, has been linked to his business dealings in Moscow. While the extent of Trumps investments in Russia is not completely known, there is evidence that Trump business have received substantial funding from Russian investors.

His charitable foundation has furthermore emerged as a phase of contention, the Washington Post reporting the coming week that Trump use $250,000 from his family charity to settle legal problems involving his own for-profit industries. The report raised questions about whether Trump, whose foundation is now the subject of a formal inquiry by the New York us attorney general, contravened US tax law.

In response to the Post, Trump spokesman Jason Miller said: There was not, and could not be, any intent or motive for the Trump Foundation to construct improper payments.

On Thursday, Oregon senator Ron Wyden, the top Democrat on the Senate finance committee, said it was imperative that Trump release his tax returns.

This is something the American people are entitled to, and the reason why is that the tax return cant spin, Wyden said. The tax return offers figures in black and white.

Read more: