The Senate largely broke along party lines Friday to vote against calling witnesses in the impeachment trial of President Donald Trump, meaning they won't hear further evidence as part of those proceedings.

But that doesn't mean the evidence won't come out in the future after Friday's vote failed 49-51. In committee reports, court filings and arguments before judges, lawyers for the House have maintained that just because the Senate began its impeachment trial doesn't mean the inquiry into alleged wrongdoing surrounding Trump's freeze of Ukrainian military aid is finished.

Rep. Adam Schiff, the lead House manager, indicated those efforts aren't over in his closing arguments in favor of hearing from witnesses Friday.

"The facts will come out. In all of their horror, they will come out," Schiff told the Senate. "There are more court documents and deadlines under the Freedom of Information Act. Witnesses will tell their stories in future congressional hearings, in books and in the media."

Reports from the House Intelligence and Judiciary committees released last month each separately said lawmakers will continue to investigate allegations Trump inappropriately withheld military aid from Ukraine while pushing the country's leaders to open investigations into the Bidens.

At the same time, more than a dozen public records lawsuits have been filed in the U.S. District Court for the District of Columbia for documents relevant to the Ukraine inquiry. Judges have granted rare preliminary injunctions for federal agencies to quickly release those documents, and more records on Ukraine are expected to be made public in the coming weeks and months.

It's an open question as to whether the House will seek to hear from some of the witnesses Republican senators declined to subpoena. It could be a tough political argument to make, that lawmakers should focus on conduct that was already the subject of a Senate impeachment trial. But it may prove just as difficult to argue that Democrats should drop the probe, as they claim there is further evidence of wrongdoing by Trump.

Jeff Robbins, a partner with Saul Ewing Arnstein & Lehr who previously worked as chief counsel for Democrats on the Senate Permanent Subcommittee on Investigations, said some Democrats may refuse to drop the Ukraine inquiries.

"It's hard for me to believe the Intelligence Committee and the House Oversight Committee are just going to walk away from the evidence that's sitting out there, behind a locked door," Robbins said.

He predicted that, if Democrats seek testimony from such figures as former national security adviser John Bolton and acting chief of staff Mick Mulvaney, the Trump White House will continue to deny those requests and potentially set off another round of court fights. However, Robbins said the existing legal fights could set the stage for future witness battles to move faster through the courts.

House managers had seized on bombshell reporting on Bolton's upcoming book, which reportedly includes recollections of Trump directly tying a hold on Ukrainian military aid to investigations into the Bidens, to argue for Bolton and others to be called as witnesses in the Senate trial.

"The obvious place to start would be to try to get Bolton to testify," said Michael Stern, who previously worked as a senior counsel to the House's office of general counsel. "But unless he's willing to do so voluntarily, it's hard to imagine they would try to enforce a subpoena at this point. But again, that's really political."

If the Senate, as it's expected to, rejects the second article of impeachment for obstruction of Congress over the White House's refusal to cooperate with the impeachment inquiry, legal experts warn it could damage lawmakers' investigative authorities in the future.

Frank Bowman, an impeachment expert and law professor at the University of Missouri, warned against that outcome in a piece for The Atlantic this week: "If the Senate, or its Republican members, accept the devious justification for defiance of Congress offered by Trump's lawyers, they will validate a strategy of complete obstruction of congressional inquiries by this and future presidents. The result is not only to neuter the impeachment power, but more profoundly, to cripple the fundamental check on executive mismanagement, abuse, corruption, and overreach embodied in their own power of oversight."

The House also has two impeachment-related lawsuits currently awaiting decisions at the U.S. Court of Appeals for the D.C. Circuit, one for former White House counsel Donald McGahn's testimony and another on grand jury information redacted from the Mueller report. McGahn has since returned to Jones Day.

The House has argued that future articles of impeachment against Trump aren't off the table, and the information is needed for that purpose as well as investigations into "presidential misconduct."

"The withheld material remains central to the committee's ongoing inquiry into the President's conduct," the House lawyers wrote in a separate briefing on the Mueller grand jury case. "If this material reveals new evidence supporting the conclusion that President Trump committed impeachable offenses that are not covered by the articles adopted by the House, the committee will proceed accordingly—including, if necessary, by considering whether to recommend new articles of impeachment."

Stern said that because the Mueller grand jury and McGahn cases are not rooted in the Ukraine investigation, it may be easier for the House to separate them from this impeachment trial and argue that they are still ongoing issues that need to be resolved.

That argument could be harder to make in seeking the Mueller grand jury information. House lawyers have been telling the court they should rule that impeachment is a judicial proceeding, one of the few times that grand jury materials can be released to another party.

Legal experts didn't rule out judges using the end of the trial to rule against the House over the grand jury materials.

But they said the House's right to oversight and conduct investigations into the executive branch, as upheld in federal court, may be enough to allow that case to move forward and is certainly enough to support the argument for the enforcement of the subpoena seeking McGahn's testimony.

Trump lawyers' arguments on whether the House should have fought to enforce the subpoenas in court have been spotlighted during the impeachment trial. Trump's impeachment counsel have said the House should have sued, while DOJ lawyers argued on Trump's behalf that the House shouldn't be allowed to go to court in the first place.

The conflicting claims were raised in a federal courthouse in Washington, D.C., on Thursday, as House and DOJ lawyers argued over a subpoena issued for documents relating to the failed effort to include a citizenship question on the 2020 census.

U.S. District Judge Randolph Moss suggested that both parties were trying to have it both ways, noting the Trump lawyers' conflicting stances as well as the House's attempt to simultaneously fight for subpoenas in court and also impeach the president.

"We are hypocrites, and they are hypocrites, I guess," Justice Department attorney James Burnham joked.

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