Shamed into it by DC & MD attorneys general? (DC Atty. Gen. told WaPo June 12 that “We’re getting in here to be the check and balance that it appears Congress is unwilling to be”. ) At the very least: "gone viral", or "doh why didn't we think of this sooner?"

By Tom Hamburger & Karen Tumulty @ The Washington Post, June 14

Nearly 200 Democratic members of Congress agreed to file a lawsuit Wednesday against President Trump alleging that by retaining interests in a global business empire he has violated constitutional restrictions on taking gifts and benefits from foreign leaders.

The lead senator filing the complaint in federal district court, Sen. Richard Blumenthal (D-Conn.), said Tuesday that the lawsuit has already drawn more congressional plaintiffs — 196 — than any legal action previously taken against a president. No Republicans had joined in the lawsuit so far, although they will be invited to do so, Blumenthal said.

An advance copy of the legal complaint reviewed by The Washington Post argues that those in Congress have special standing because the Constitution’s “foreign emoluments clause” requires the president to obtain “the consent of Congress” before accepting any gifts [....]