WASHINGTON (AP) — House Speaker Nancy Pelosi has introduced a new concept into the debate over President Donald Trump’s actions: “self-impeaching.”

As Trump all but goads Democrats into impeachment proceedings, viewing the showdown as potentially valuable for his 2020 re-election campaign, Democrats are trying to show restraint. Their investigations are both intensifying but also moving slowly as Democrats dig into the special counsel’s Trump-Russia report and examine Trump’s finances and governance.

The more they push, the more Trump resists, the president making what Pelosi says is his own case for impeachment with his stonewalling of Congress.

“The president is self-impeaching,” she told her colleagues last week during a private caucus meeting, echoing comments she also aired in public. “He’s putting out the case against himself. Obstruction, obstruction, obstruction.”

There is no actual process for self-impeachment. It’s a thought bubble more than a legal term. A pure Pelosi-ism, one that an aide says she coined herself. But as a device, it’s a way for Pelosi to frame the often complicated idea of the White House refusing to engage with Congress in the traditional process of checks and balances.

“Sometimes people act as if it’s impeachment or nothing,” Pelosi told reporters. “No, it’s not that. It’s a path that is producing results and gathering information.”

In the aftermath of special counsel Robert Mueller’s investigation, the slow drip of congressional oversight also serves a dual purpose politically. It allows Democrats to keep impeachment proceedings at bay, despite calls to push ahead by the liberal flank, while stoking questions about Trump going into the 2020 presidential election.

They note the Watergate investigation dragged on two years before the House Judiciary Committee opened impeachment proceedings against President Richard Nixon. By the time articles of impeachment were drawn up, the third entry was Nixon’s obstruction of Congress.

So far, House committees have issued multiple subpoenas for executive branch information, including for an unredacted version of the Mueller report and some million of pages of underlying evidence; for testimony and documents from former White House counsel Don McGahn; for information on Trump’s business dealings; and for Trump’s tax returns.

“My Democratic colleagues seem to be publicly working through the five stages of grief,” Senate Majority Leader Mitch McConnell mused in a floor speech. As McConnell declared “case closed,” he noted the final stage of grief is acceptance.

Except Mueller’s 448-page report left Congress with questions. While the special counsel found no evidence the Trump campaign colluded with Russia to swing the 2016 election, Mueller did not render a decision on whether the president obstructed justice. “It also does not exonerate him,” the report says.

At least one Republican, Sen. Richard Burr of North Carolina, chairman of the Senate Intelligence Committee, appears to have questions, too. His committee issued a subpoena for testimony from one of the president’s sons, Donald Trump Jr. The move sparked blowback among allies of the White House and divided Senate Republicans into two camps: those who backed his oversight role and those who panned it.