Protesters hold up placards outside the Mar-a-Lago estate to call on President Donald Trump to release his tax records as they cross the bridge into Palm Beach, Florida on April 15, 2017. That number comes from a MoveOn.Org poll. Several prominent Democrats have promised to not engage with the GOP on tax reform, the next point on the Trump administration's policy agenda, until Trump releases his returns.
Mr Spicer has previously claimed that the level of transparency displayed by Mr Trump "exceeded any modern president in terms of who's involved".
Of course, for the thousands who marched over the weekend, this response from Trump was flawless - an indication that their efforts had not gone unnoticed by the egotistical leader. "I became president. I don't think they care at all". In fact, almost 400,000 Americans have signed a Change.org petition calling for Trump to release his taxes.
Joe Dinkin, spokesman for the Working Families Party, one of the groups organizing the marches, said investigations into the Trump campaign's alleged connections to Russian Federation underscore the need to disclose his returns. Surely he's not being audited for this year, yet. "We're under the same audit that existed, and so nothing has changed".
Three Republicans from the House Freedom Caucus - Rep. Mark Sanford, Rep. Ted Yoho and Rep. Justin Amash - have signed onto a Democratic measure to force the release of Trump's returns.
Last month, tax expert David Cay Johnston revealed that Trump paid $38 million in federal tax on $150 million in income in 2005.
A resident at Cotton's town hall Monday said that Trump's tax returns would expose his overseas interests - a hint at the central role Trump's tax returns have taken in the continuing investigations into Russia's meddling with U.S. elections.
Asked in a later exchange if we can assume Trump will never release his returns, Spicer said he would "get back to you on that".
In his daily press briefing Monday, Spicer was asked specifically if Trump will ever make his tax returns public. "Now Tax Returns are brought up again?" he tweeted earlier Monday.
Americans are putting the finishing touches on their 2016 tax returns in anticipation of Tax Day Tuesday.