Treasury Secretary Steve Mnuchin sent a letter to House Ways and Means Chairman Richard Neal (D-Mass.) Tuesday informing him that the Treasury Department will decide by May 6 whether to release President Trump's tax returns to Congress — effectively ignoring the April 23 deadline that Neal had set.

"Due to the serious constitutional questions raised by this request and the serious consequences that a resolution of those questions could have for taxpayer privacy, the Department is consulting with the Department of Justice. Although federal law establishes no deadline for a response to your request, we expect to provide the Committee with a final decision by May 6, after receiving the Justice Department's legal conclusions."

The big picture: In the past few days, the Trump administration has taken a number of steps to block oversight by House Democrats, or — as the president and his defenders have labeled it — "presidential harassment."