Senior Democratic lawmakers are due to speak at a march on April 15 ― the day when Americans’ tax returns are typically due ― to demand that President Donald Trump release his tax returns.

“The Tax March,” as the progressive groups organizing it have dubbed it, will begin with a rally and speeches at the U.S. Capitol, followed by a parade that passes the Trump International Hotel, as well as the FBI and IRS buildings. Over 100 smaller marches are due to take place in cities across the country.

Sen. Ron Wyden (D-Ore.), ranking member on the Senate Finance Committee; Rep. Maxine Waters (D-Calif.), ranking member on the House Financial Services Committee; and Rep. Jamie Raskin (D-Md.) will join a host of faith, policy and grassroots leaders scheduled to speak on Trump’s continued lack of financial transparency.

“I am proud to join Americans across this country in holding Trump accountable for deceiving the American people and refusing to tell the truth about his financial entanglements and conflicts of interest,” Rep. Waters said in a statement announcing her participation. “He should have to face the consequences of trying to hide from the American public.”

A broad of array of liberal groups and labor unions are convening for the Tax March, including MoveOn.org, Public Citizen, Demos, Credo, the Working Families Party, the National Women’s Law Center and the American Federation of Teachers. 

They also plan to address what they believe are the inequities of the current tax system.

“Donald Trump and his billionaire Cabinet are proposing even bigger tax cuts for the wealthy when what we need is a fairer system that allows our nation to meet the needs of its people,” Demos president Heather McGhee said in a statement.

Although the date of the march was chosen because it is usually Tax Day, this year individual tax returns are due on Tuesday, April 18. April 15 is a Saturday and the following Monday government workers have off for Emancipation Day, a federal holiday.

It is extremely unlikely that a liberal protest march will prompt Trump to release his tax returns. The day’s actions are instead aimed at reminding the public of Trump’s historic lack of transparency at a time when the president is struggling politically.

Trump is the first president in four decades who has not released his tax returns or comparable financial information. The practice became a tradition when former President Richard Nixon released his returns after he was audited.

Critics have wondered if Trump has something to hide by refusing to disclose information about his finances, such as whether he is violating the Constitution’s Emoluments Clause prohibiting a president from receiving foreign gifts or payments. The opacity of Trump’s finances also makes it impossible to know whether he has a financial stake in pursuing certain policies.

White House officials insist that Trump has no plans to release the returns. Senior adviser Kellyanne Conway claimed in January that Trump’s election showed that the public does not care.

Congressional Republicans have voted down Democrats’ efforts to use obscure legal provisions to compel their disclosure.