Congress is taking its first steps toward a potentially massive investigation into the failures that contributed to the Capitol insurrection on Jan. 6. But its initial foray only underscored how little lawmakers — and the public — know about what truly transpired that day.

Five hours of Senate testimony on Tuesday from top security officials only added to the mounting questions about an attack by supporters of former President Donald Trump that threatened an entire branch of government.

Here’s what we've learned so far — and just as importantly, what investigators left for another day:

Pentagon and Homeland Security officials need their turn ...

Senate leaders from both parties always intended for the inquiry to press on with additional hearings, and they came away with obvious investigative leads on Tuesday.

Almost immediately after the joint oversight hearing began, senators were calling for testimony from senior officials at the Pentagon, FBI and Department of Homeland Security, some of whom were directly implicated by the four witnesses: former Capitol Police Chief Steven Sund, former House Sergeant-at-Arms Paul Irving, former Senate Sergeant-at-Arms Michael Stenger and acting D.C. police chief Robert Contee. Even though that group largely passed the buck to other federal agencies and departments, the current and former officials gave lawmakers new lines of inquiry to pursue.

In particular, the witnesses described intelligence breakdowns as well as bureaucratic delays from the Defense Department that left them unprepared to defend the Capitol from the violent mob.

Sund and Contee described a conference call during which top Pentagon leaders said they worried about the “optics” of sending armed troops to the Capitol, even as the police chiefs said their respective forces were desperate for backup.

Sund said it took at least two hours for their request to be run up the chain of command at the Pentagon. Contee told senators he was “literally stunned” at the response from the Defense Department.

In addition, all four witnesses agreed that the intelligence they were given ahead of time did not point to the types of violence and outright lawlessness that officers confronted on Jan. 6.

... and they'll get it soon

Those revelations prompted the Democratic chairs of the two committees spearheading the probe — Gary Peters of Michigan and Amy Klobuchar of Minnesota — to immediately seek testimony from the officials in question. Though they declined to name specific individuals, Peters and Klobuchar said they plan to convene another hearing next week, and that it would feature Pentagon, Homeland Security and FBI officials.

“There were clearly mistakes made on many sides, but it’s also on their front, what happened with the National Guard,” said Klobuchar, who chairs the Rules Committee. “And while they should have been set up ahead of time — that is true given some of the intelligence out by Jan. 3 — why, that day, was there a delay?”

Sen. Roy Blunt of Missouri, the top Republican on the Rules Committee, went as far as to posit that the Capitol Police’s entire structure is “almost totally unworkable in times of crisis,” and that the logistical hurdles “actually got in the way” of coordinating with federal entities outside of the Capitol.

Still, Blunt said he wants to question the FBI next week about possible intelligence failures that prevented Capitol security officials from adequately preparing for the events of Jan. 6.

One big discrepancy, and multiple mysteries, remain

Senators largely failed to procure new information out of their witnesses beyond what they divulged in lengthy and at times contradictory opening statements. The most glaring discrepancy: that Sund claimed he spoke to Irving at 1:09 p.m on Jan. 6 and requested National Guard help, while Irving insisted he was on the House floor at the time and received no call — from Sund or anyone else.

Irving appears to be at least partially correct: C-SPAN video shows he was on the floor at the precise moment the clock struck 1:09 p.m. But senators never raised that fact, and they were often so rushed to squeeze in multiple strains of questions that they left essential information unaddressed.

In addition, not a single member asked some of the most burning questions of the entire inquiry:

— What was the cause of Capitol Police officer Brian Sicknick’s death?
— What is the status of any review of lawmakers’ relationships to some of the rioters, including allegations that some may have been given tours of the building on Jan. 5?
— What is the basis for the Capitol Police’s ongoing investigations of 35 officers for their conduct on Jan. 6?

Remarkably, the cause of Sicknick’s death has remained a mystery even as it’s become a symbol of the intense violence of the Trump-inspired riot for the past 48 days. And lawmakers passed on a chance to nudge more details out of the notoriously secretive Capitol Police.

March 4 fears get short shrift

Sen. Jacky Rosen (D-Nev.) concluded her questioning with a request for information about potential violence on March 4 — the Constitution’s original inauguration day — which authorities have warned could feature another attempted attack by those who refuse to accept the election results. What, she asked, was being done by authorities in Washington to prepare?

But as law enforcement officials started to respond, Rosen’s time expired. Klobuchar ushered the hearing to the next scheduled senator, Mark Warner, leaving Rosen’s question unanswered.

Johnson's alone in his theory

Sen. Ron Johnson (R-Wis.) used part of his time during Tuesday's hearing to read a discredited conspiracy theory into the record. Quoting generously from a conservative commentary piece that attributed the Jan. 6 insurrection to overaggressive police and a band of provocateurs posing as Trump supporters, Johnson showed that he’s on an island among his Senate colleagues pushing that notion.

All four of the security officials had rejected his perspective before Johnson even spoke. But none of them had to: The overwhelming record of violence that prosecutors have begun compiling in court has already shown Johnson's suggestion to be false. Investigators have been piecing together evidence to show that significant elements of the Jan. 6 insurrection were pre-planned and coordinated among extremist groups that considered themselves aligned with Trump.

And all four witnesses were clear that they considered the Jan. 6 event to be an insurrection aided by white supremacists.

Honoré's about to face friction

Republicans have been sharply critical in recent days of retired Lt. Gen Russel Honoré, Speaker Nancy Pelosi’s pick to conduct an interim review of Capitol security following the insurrection.

Past tweets and commentary from Honoré show he was harshly critical of Sund, the sergeants-at-arms and of the police officers themselves, calling them complicit in the violence by virtue of their actions. Honoré had also attacked Republicans who led the charge to challenge the certification of the 2020 election results, including suggesting that Sen. Josh Hawley (R-Mo.) should be driven out of D.C. for contesting the certification.

Under questioning from Hawley and later from Sen. Bill Hagerty (R-Tenn.), the witnesses repudiated Honoré’s comments.

Sund called Honoré's comments “highly disrespectful to the hardworking women and men" of the Capitol Police.

The exchange underscores that Honoré is likely to take further political heat as he prepares to render judgment about future plans for Capitol security.

Trump's a non-entity so far

One name that didn’t come up much during the hearing? Trump. Though the House impeached Trump for inciting the insurrection, a move followed by acquittal in a Senate trial, the impeachment itself was only sparingly mentioned and his role minimally discussed.

Trump came up when Sund emphasized that only the ex-president, who controlled D.C.’s National Guard forces, had the ultimate authority to deploy those troops when the Capitol was in danger. But there was little effort to probe the former president’s actions, and no witness indicated they had any knowledge of whether the president himself was weighing in on security issues as they pleaded for assistance.

In the shadow of Joe Biden’s inauguration as the 46th president of the United States, the Senate is set to put his predecessor on trial for high crimes and misdemeanors — potentially barring him from holding federal office ever again.

The House impeached President Donald Trump last week for “willful incitement of insurrection,” a grave charge that stems from the president’s encouragement of rioters who on Jan. 6 stormed the Capitol based on the false notion that the 2020 presidential election was “stolen.” The insurrection left five people dead and countless others injured.

The trial’s exact start date isn’t yet certain. Speaker Nancy Pelosi has not formally transmitted the impeachment article to the Senate — a move that, according to the Senate’s rules, triggers the start of the trial on the very next day. Pelosi’s deputies have said she will send the article across the Capitol “soon” but have not given a specific timeline.

Here’s everything you’ll need to know once the trial gets underway.

Can the Senate hold a trial for an ex-president?

It’s the debate that has been raging in legal and constitutional circles for a week: Does the Senate have any business deploying its most potent punishment against Trump as a private citizen?

One camp, personified by Sen. Tom Cotton (R-Ark.), says no: “The Founders designed the impeachment process as a way to remove officeholders from public office — not an inquest against private citizens.” In other words, you can’t remove from office someone who has already relinquished the office.

The other view, given voice in a recent op-ed by Steve Vladeck, a University of Texas law professor, says that of course a former president can be convicted. The Constitution doesn’t just provide for removal but also for the Senate to bar that former president from ever holding federal office again. In Vladeck’s view, how could the framers have designed a “disqualification” system that could be defeated if the target simply resigned minutes before the process was complete?

The bottom line is this: Congress, by deciding to hold an impeachment trial after Trump’s exit, is daring the courts to wade into territory that judges typically avoid. The Constitution gives the House and Senate the “sole power” to handle matters of impeachment. Judges have frequently cited this to determine that they have no role in telling lawmakers how to wield their own constitutional power. It’s safe to think they’ll end up there again.

Will the 2021 trial work differently than last year’s?

A year ago, Congress spent the first full day of Trump’s impeachment trial in a fierce battle over the rules, which dictate the entire course of the trial. Back then, conviction was a nonstarter — most Republican senators had pretty much ruled it out from the start, and the major questions were how uncomfortable Democrats could make them before they summarily let Trump off the hook.

This time, with a slew of undecided senators — including Mitch McConnell of Kentucky, the outgoing majority leader — the rules loom even larger.

One thing to watch for: Do Republicans like Sen. Lindsey Graham (R-S.C.), who oppose the trial, try to force a vote on dismissing the charges? If they do, it will probably fail since the Senate will be split 50-50 along party lines, and enough Republicans have signaled openness to conviction that they’re unlikely to end the trial before it begins. But that vote could also be an early test for just how many Republicans might be open to conviction.

After sweeping aside any dismissal attempt, the Senate must determine how much time to give each side to lay out its arguments. In 2020, it was 24 hours apiece. Seven House impeachment prosecutors and a team of veteran White House and constitutional lawyers spent six days offering their cases. This time, Pelosi has selected nine impeachment managers and Trump hasn’t even identified a legal team to deliver his case.

Rep. Jamie Raskin (D-Md.), the lead impeachment manager, has not tipped his hand on specific strategies, but he has offered this broad exhortation: “We just want the Senate to conduct a serious trial where every member of the Senate lives up to his or her constitutional oath to render impartial judgment as a juror.”

One unusual aspect of this trial? Every impeachment manager and every juror was also a victim of the alleged crime: incitement of insurrection. The same people trying and deciding the case were the ones ducking behind chairs and dodging violent mobs less than two weeks ago, while they frantically pleaded with Trump for help that only belatedly arrived.

Raskin intends to lean on that experience as he tells a big-picture story about the insurrection as an “attack on our country.”

“There are thousands of people that work on Capitol Hill, not just members but staff members, and Capitol Hill police officers, who were pushed and shoved and punched in the face, pummeled and hit over the head with fire extinguishers,” Raskin said Sunday on CNN’s “State of the Union.” “And the president did nothing to stop it for more than two hours as members of Congress called him and begged him to do something and he continued to watch it on TV and enjoy their insurrection tailgate party.”

Democrats will also point early and often to the arguments lodged by the 10 Republicans in the House who voted to impeach Trump, including Rep. Liz Cheney of Wyoming, the No. 3 House Republican.

Last time, Democrats also sought to empower Chief Justice John Roberts — required by the Constitution to preside over presidential impeachment trials — to decide matters of executive privilege. But Republicans rejected the suggestion, and Roberts himself signaled he intended to play a low-key role.

How likely is a conviction?

Make no mistake about it: The House impeachment managers face an uphill climb as they try to persuade enough senators to vote in favor of conviction. Last year, there was virtually no chance that the Senate would reach the two-thirds threshold required, but this year, it seems at least possible that at least 17 Republicans could join all 50 Democrats to vote to convict.

For starters, McConnell has adopted a markedly different posture. Ahead of the last trial, McConnell said there was “no chance” Trump would be booted from office and was a key defender of the president. But this time around, McConnell is keeping an open mind and is urging his fellow GOP senators to keep their powder dry. It could mean that Sen. Mitt Romney of Utah, the only Republican who voted to convict Trump in the first impeachment trial, will have company this time around.

Trump’s exit from the White House alone isn’t likely to be a good enough reason for Republicans to feel comfortable with voting to convict him. Even though the president will be out of office by the time the Senate votes on conviction, he will remain a force within the GOP for years to come, and he has pledged to remain involved in campaigns. A chief concern for Republicans facing reelection in 2022 and 2024 is that Trump could back a primary challenger.

Still, convicting Trump and barring him from holding federal office could clear a pathway for the countless Republicans considering seeking the GOP presidential nomination in 2024, many of whom serve in the Senate. If Trump decided to run for president again in 2024, he could be the favorite to secure the party’s nomination.

McConnell will be the most important person to watch in determining whether the Senate has the votes to convict Trump. If he votes “yes,” it’s easy to see at least 16 other Republicans joining him. If he doesn’t, conviction becomes much less likely.

Will the House managers attempt to call witnesses?

At last year’s trial, Democrats were pressing vigorously for the Senate to hear testimony from additional witnesses who could shine light on Trump’s alleged misconduct. But this year, it might not be in Democrats’ interest to push for witnesses.

Democrats have raised concerns about holding a trial in the opening days of Biden’s presidency because it would delay Senate action on staffing his Cabinet and considering additional Covid-19 relief legislation.

At the same time, with so many Republicans appearing open to conviction this time around, it might be beneficial for the House impeachment managers to be able to call witnesses, especially because the House did not conduct a formal impeachment inquiry before last week’s vote.

For now, the House impeachment managers are remaining mum about their strategy when it comes to witnesses. Democrats have maintained that a full investigation is not necessary because the evidence for impeachment is in the public domain — and lawmakers themselves were witnesses to an insurrection that put their lives in danger.

“The last [impeachment trial] was information brought to us by others,” said Sen. Debbie Stabenow of Michigan, the No. 4 Senate Democrat, in an interview. “This is an impeachment based on what we experienced, and what the president of the United States said, in speeches, that day, that were videotaped. All the evidence is really right in front of us.”

Indeed, senators themselves were forced to hastily evacuate the Senate chamber and were just feet away from the violent mob that eventually made its way onto the Senate floor. During last year’s trial, the House managers used several audio and video clips to aid their legal arguments; this year they’re likely to use to their advantage the hours of troubling footage showing the rioters desecrating the Capitol, violently beating police officers and rummaging through the Senate chamber — in addition to clips of Trump’s remarks ahead of the storming of the Capitol.

One potential witness on Democrats’ list is Brad Raffensperger, the Georgia secretary of state. Trump has mercilessly harangued Raffensperger and Gov. Brian Kemp, who are both Republicans, for not adopting his unsubstantiated claims of voter fraud in the state. Earlier this month, the president held an hourlong phone call with Raffensperger during which Trump pressured the secretary of state to “find” votes on his behalf to overturn Biden’s victory in Georgia.

Prosecutors in Atlanta are reportedly considering opening a criminal investigation into Trump over his pressure campaign.

Still, Democrats might reject outside witnesses in the name of completing the trial more quickly.

“We have so much to do,” Stabenow added. “There's no reason to spend time that isn’t necessary. We need to follow the law and the Constitution, treat this with seriousness. And the process needs to have integrity. At the same time, we need to have it move along in a way that will allow it to be completed so that we can continue the other critical things that have to get done for the country.”

Disarray on the president’s legal team

In previous years, a chance to represent presidents would be a lawyer’s dream, a crowning career achievement that could also mean lucrative professional opportunities in the future. But Trump has proven to be a difficult client and, in this case, a toxic one. Few appear to be lining up to eagerly combat charges that the president — through a monthslong campaign of false and pernicious claims of election fraud — motivated the frothing Jan. 6 mob to attack the Capitol and hunt down Pelosi and Vice President Mike Pence.

In 2020, Trump recruited former independent counsel Ken Starr and Harvard law professor Alan Dershowitz to mount big-picture legal arguments, which were effective with some open-minded senators. He also had veteran White House lawyers Pat Cipollone and Patrick Philbin at the defense table, along with outside counsels Jane and Marty Raskin, former Florida Attorney General Pam Bondi and conservative lawyer Jay Sekulow.

This time, none of the same attorneys appear poised to return. Dershowitz has indicated he generally supports the view that Trump’s Jan. 6 remarks to the rally crowd, which later became the violent mob, are protected free speech. But he has indicated he will probably make those arguments from the sidelines this time.

That has left Trump’s personal lawyer Rudy Giuliani — whose own efforts to aid Trump’s campaign to overturn the election have drawn bipartisan scorn on Capitol Hill — as one of the only prominent figures standing in Trump’s legal defense orbit. But reports suggest that Giuliani has also been ruled out. Over the weekend, Trump campaign spokesman Hogan Gidley said Trump had simply not decided on an impeachment legal team yet.

Burgess Everett contributed to this report.

For a year, Senate Republicans have teased a bombshell investigation into Joe and Hunter Biden that could rock the former vice president’s campaign for the White House.

But an interim report, issued by Sens. Ron Johnson (R-Wis.) and Chuck Grassley (R-Iowa) less than six weeks before the presidential election and released publicly on Wednesday, is largely a compilation of previously public information — some of it rehashed anew by witnesses who already testified during the House’s impeachment inquiry last year — as well as news articles and strongly worded insinuations with little evidence to back them up.

The report, titled “Hunter Biden, Burisma and Corruption,” reprises these year-old claims and adds little new to a discussion first raised by President Donald Trump’s defense team in his impeachment trial before the Senate earlier this year, when the president was acquitted by GOP senators on charges of abusing his power by seeking to pressure Ukraine to investigate the Bidens. The report does little to substantiate allegations against the Democratic presidential nominee, which have been fueled in part by foreign actors linked to the Kremlin whom U.S. officials have said are attempting to interfere in the 2020 election.

The report relies on vague assessments already revealed publicly — namely, from top State Department official George Kent, who said Hunter Biden’s role on the board of a Ukrainian energy company was “very awkward” for U.S. officials who were carrying out an anti-corruption policy in Ukraine. Kent made a similar remark during his impeachment testimony last fall.

The report also highlights a year-old New Yorker article describing a conversation between Biden and a top aide about his son’s role on the board of the Ukrainian energy company, Burisma, but notes that the article provided no evidence about how Biden reacted. The aide, Amos Hochstein, a former special envoy for international energy in Barack Obama’s administration, declined to discuss his conversation with Biden about the subject when he testified last week before Johnson’s panel.

The GOP senators have been investigating allegations that a Democratic public-relations firm, Blue Star Strategies, sought to influence the Obama-era State Department by leveraging Hunter Biden’s role on the board of Burisma, a Ukrainian energy company. Trump has pushed Republicans to use their investigative powers to probe his political rivals.

The investigation — which lacked majority support among members of the Senate Homeland Security and Governmental Affairs Committee that Johnson chairs — found that two officials, including Kent, raised conflict-of-interest concerns to Biden when he served as vice president. The report states that Hunter Biden’s role “cast a shadow” over U.S.-Ukraine policy, but provides no evidence that U.S. foreign policy was impacted.

Democrats raised concerns that Johnson would not honor a recent committee vote to release all of the witness interview transcripts alongside the report, except for in cases where classified information might be revealed. Johnson’s staff did not immediately release full transcripts on Wednesday, only quoting from witness testimony in the report, often without full context.

Democrats, led by Sens. Gary Peters of Michigan and Ron Wyden of Oregon, accused Johnson of publicly hyping a damaging report on Joe Biden only to issue a report that included no such evidence.

"Chairman Johnson repeatedly impugned Vice President Biden in public on the basis of secret evidence he claimed to have obtained," the Democrats said. "Contrary to his public insinuations, the Chairmen’s investigation found no evidence that the former Vice President did anything wrong in his efforts to carry out official U.S foreign policy in Ukraine."

The Johnson-Grassley report devotes 10 of its 87 pages to criticizing Democratic attacks and media reports about the investigation, including several from POLITICO. And it ends stating that “there remains much work to be done,” citing lack of compliance from the executive branch.

Allegations that the Democratic firm Blue Star Strategies attempted to sway the State Department during the Obama administration follow the argument Trump’s lawyers made during Trump’s January defense against impeachment charges that he abused his power by pressuring Ukrainian leaders to investigate Biden and his son. Johnson ramped up his Biden-focused probe during the House’s impeachment inquiry and though it briefly faded from view as Biden’s presidential candidacy seemed to sputter, he intensified it again in February after Biden surged back into contention.

Trump’s allies allege that Biden — who led anti-corruption efforts for the Obama administration in Ukraine — forced the removal of a Ukrainian prosecutor who was investigating Burisma while Hunter Biden sat on the board. But high-level State Department witnesses repeatedly discredited this claim, emphasizing that Biden’s removal of the prosecutor, who was widely seen as corrupt, was official U.S. policy and actually made it likelier that Burisma would face a serious corruption investigation.

Nevertheless, Johnson pursued the allegations, even amid increasingly loud warnings — from some Republicans, too — that some of the actors perpetuating the same narrative were doing so at the behest of Russia, which intelligence officials say is interfering in the 2020 election to denigrate Biden.

As a result, Johnson’s investigation has been mired in growing controversy. Democrats have accused Johnson of aiding Vladimir Putin’s attack on American elections, a charge whose potency grew after the Treasury Department sanctioned pro-Russia Ukrainian lawmaker Andriy Derkach, calling him a Russian agent who is fueling false narratives about Biden. Senators have openly clashed in classified settings over Johnson’s probe.

In the report, Johnson and Grassley reject the notion that Derkach’s material, or any evidence he has purported to gather, made its way into their report.

“Since the offices of Chairman Johnson and Chairman Grassley did not receive, and were unaware of, the information that Derkach had allegedly sent, it is impossible that Derkach’s efforts could have shaped the committees’ investigation in any way,” they wrote.

Johnson’s allegations against the Bidens mirror those pushed by Derkach, who sent packets of information about Biden to Johnson and other Trump allies on Capitol Hill. But Johnson’s office has denied that the senator received anything from Derkach or is relying on his claims. Trump’s personal lawyer, Rudy Giuliani, has met with Derkach and sought to spur an investigation into the Bidens, led by the Ukrainian government — an effort that ultimately got Trump impeached by the House.

Derkach has been releasing leaked tapes of phone calls between Biden and former Ukrainian President Petro Poroshenko, none of which support the narrative Derkach has pushed but which have fueled fear of a high-level plot. Trump has amplified reports about those tapes despite warnings about Derkach from the intelligence community.

In a statement, Biden campaign spokesman Andrew Bates said Johnson has “wasted months” investigating the Bidens while the coronavirus pandemic rages. He said Johnson sought to “subsidize a foreign attack against the sovereignty of our elections with taxpayer dollars — an attack founded on a long-disproven, hardcore rightwing conspiracy theory.”

The report leans heavily on 100 citations from 14 "confidential documents" in lengthy passages detailing Hunter Biden's financial connections to foreign nationals. The documents are actually Suspicious Activity Reports kept by the Treasury Department, in which financial institutions flag transactions but don't verify whether any wrongdoing has occurred. Peters said the GOP senators' decision to rely on these reports, and publicize their details without any independent investigation, was an unprecedented use of congressional power.

In addition, Democrats emphasized that the reports were "generated at the request of law enforcement" in the fall of 2019, an unusual development for reports typically created by the financial institutions themselves. "Specific details about which law enforcement personnel requested the documents were redacted," the Democrats noted.

"The Republican Chairmen’s use of confidential Treasury documents to justify its unsubstantiated allegations and personal attacks against Vice President Biden’s family is grossly irresponsible," the Democrats said. "The information in the documents cited by the Republicans has not been verified, and we are not aware of any other Congressional committee ever releasing this sort of information in this manner."

It's unclear if the documents refer to bank statements or government filings or other materials that would help provide a roadmap for how the committee investigated the son of the former vice president.

Despite the release of what Johnson dubs an “interim” report on Wednesday, he has faced several roadblocks in recent months.

Earlier this year, Johnson tried to issue a subpoena to Andriy Telizhenko, a former Ukrainian diplomat who has pushed unsubstantiated claims about Ukrainian interference in the 2016 election. But he ultimately scrapped the subpoena after the FBI’s Foreign Influence Task Force briefed committee aides about Telizhenko, prompting unease among Republicans.

For months, Johnson pushed back on the idea that his probe was intended to help Trump politically. But more recently, he has confirmed those suspicions.

“People need to take a look at this report very carefully and understand what the ramifications are for electing Joe Biden as president,” Johnson said on a local radio program Tuesday, the day before he released the report.

Indeed, some of Johnson’s fellow Republicans have criticized the investigation as a political exercise, including Sen. Mitt Romney (R-Utah), who sits on the Homeland Security panel. Romney was the only Republican to vote to convict Trump during the Senate impeachment trial.

“It is not the legitimate role of government, for Congress or for taxpayer expense, to be used in an effort to damage political opponents,” Romney said last week.

Other Republicans have distanced themselves from Johnson’s actions, refusing to defend the investigation but declining to openly criticize it. POLITICO previously reported that Sen. Richard Burr (R-N.C.), the former chairman of the Senate Intelligence Committee, confronted Johnson privately about the probe, telling the Wisconsin Republican that it could aid Russia’s election-meddling efforts.

Still, Johnson has pressed on, as Trump’s allies pressured him to keep the heat on the Bidens. Johnson has also launched a separate investigation centering on the Obama administration’s actions during the presidential transition period, stemming from the FBI’s counterintelligence investigation in 2016 that targeted the Trump campaign.

The State Department on Friday turned over 16,000 pages of documents to a House committee that were previously given to Senate Republicans investigating Joe and Hunter Biden — providing Democrats with key information as a top GOP senator prepares to release a report expected to be highly critical of the Democratic presidential nominee.

The massive document production to the House Foreign Affairs Committee led Chairman Eliot Engel (D-N.Y.) to rescind his July subpoena for the documents and pause the panel’s contempt proceedings against Secretary of State Mike Pompeo.

It also comes as Sen. Ron Johnson (R-Wis.), who is leading the GOP probe targeting the Bidens, is teasing a forthcoming report detailing the allegations, which center on Biden’s son Hunter and his role on the board of Burisma, a Ukrainian energy company. Johnson has said his report is likely to be published next week.

Democrats have described Johnson’s probe as a politically motivated smear campaign against President Donald Trump's challenger that has already been discredited and tainted by Russian propaganda. The intelligence community has identified a pro-Kremlin Ukrainian lawmaker, Andriy Derkach, as an agent of a Russian disinformation campaign intended to denigrate Biden.

“This ‘investigation’ is obviously designed to boost the president’s campaign and tear down his opponent, while our own intelligence community warns it is likely to amplify Russian disinformation,” Engel said in a statement. “We’re going to make sure the American people see the whole picture, not just cherrypicked information aimed at breathing new life into debunked conspiracy theories.”

Democrats have raised concerns that material gathered by Derkach, who met in December with Trump’s personal lawyer Rudy Giuliani, has been laundered into Johnson’s material. Johnson has strenuously denied the allegations, but Democrats sought the documents he obtained from the State Department to understand the direction his probe is taking. POLITICO first reported that Derkach mailed information about the Bidens to Johnson, but Johnson’s office has denied receiving anything from Derkach.

Derkach has pushed many of the same claims against Biden that Johnson, who chairs the Senate Homeland Security and Governmental Affairs Committee, is pursuing. Johnson’s probe centers on allegations that a Democratic public-affairs firm sought to leverage Hunter Biden’s position on the board of Burisma in order to influence the Obama-era State Department.

Johnson has also alleged that Hunter Biden’s role was itself a conflict of interest because his father, who at the time was the vice president, was spearheading U.S. policy toward Ukraine.

Johnson has drawn condemnation in recent weeks for characterizing his probe as potentially fatal to Biden’s presidential candidacy, a political calculation that Democrats said removed any doubt about the goal of his investigation.

Some Republicans have expressed discomfort with Johnson’s probe, too. Sen. Mitt Romney (R-Utah) last week described it as a “political exercise” and said he opposed Johnson’s efforts to subpoena additional witnesses as part of the investigation. POLITICO reported earlier this year that Sen. Richard Burr (R-N.C.), then-chairman of the Senate Intelligence Committee, warned Johnson that his probe could aid Russia’s election-meddling efforts.

“It is not the legitimate role of government, for Congress or for taxpayer expense, to be used in an effort to damage political opponents,” Romney said this week, referencing Johnson’s earlier comments that called into question the Wisconsin Republicans’ assertions that the investigation has nothing to do with the upcoming election.

Engel has accused the State Department of racing to aid Johnson’s effort despite stonewalling House Democrats in numerous other investigations, including its impeachment inquiry in 2019. He cited a recent internal directive, revealed last month by POLITICO, that urged state Department offices to provide key documents to Johnson by the end of September.

Two key Republican senators on Tuesday raised alarm about President Donald Trump’s recent hostility toward the government’s internal watchdogs, tacitly warning that he has threatened their independence and asking the president to support, rather than undermine, them.

In a letter to the president, Sens. James Lankford (R-Okla.) and Rob Portman (R-Ohio) also urged Trump to nominate permanent officials to fill the powerful positions, rather than relying on temporary fill-ins that circumvent the Senate’s traditional confirmation process.

“Recent statements and actions in the administration have raised concerns on Capitol Hill and among the IG community about the administration’s support for IGs and the statutory authorities Congress has granted them,” the senators wrote — a reference to Trump’s amped-up hostility toward inspectors general in recent days that has prompted many of his congressional allies to speak out against him in rare form.

“We would hope the White House would view IGs as your partners in objectively identifying and rooting out waste within the federal government,” Lankford and Portman added.

Their plea for support of the dozens of inspectors general throughout the government comes one day after Trump blew past a deadline to provide a bipartisan group of senators with a fuller explanation of his decision to fire the intelligence community’s inspector general, Michael Atkinson, late at night on April 3.

The GOP senators’ gentle rebuke of Trump is the latest in an unusually concerted push by Democrats, Republicans and the federal watchdog community overall to brush back the president for his incursion on the independence of inspectors general.

And it came just minutes before a bipartisan duo, Sens. Chuck Grassley (R-Iowa) and Ron Wyden (D-Ore.) wrote to Michael Horowitz, who leads the council of inspectors general, demanding information about the White House’s process for vetting and submitting nominees for confirmation by the Senate.

Atkinson, who was nominated by Trump and later confirmed by the Senate, provoked the president’s fury by informing Congress of a whistleblower complaint that led to his impeachment in December. Trump also sidelined Glenn Fine, the former acting Pentagon inspector general expected to lead oversight of the $2.2 trillion coronavirus emergency relief measure, effectively demoting him just days after his fellow inspectors general picked him for the role.

Trump’s recent actions have galvanized an unlikely coalition of critics, headlined by several of his longtime congressional who are often loath to criticize him, even indirectly.

In their letter, Lankford and Portman specifically asked Trump to protect and support whistleblowers, whom they said “play a key role in assisting IGs identify waste, fraud, and abuse.”

“We encourage you to send a strong message to the executive branch to work with IGs, not against them,” the senators added.

Trump has also assailed the Health and Human Services Department’s watchdog — who has spent 21 years serving administrations of both parties — attacking her as a political operative over her finding that hospitals across the nation were unprepared for the coronavirus crisis.

And Trump has threatened another core function of inspectors general, telling Congress last month that he is the ultimate authority on whether federal watchdogs — technically employees of the Executive Branch — can share certain findings with lawmakers. Portman and Lankford indicated they were particularly concerned about the ability of inspectors general to report their findings in an “unbiased” way to Congress, pointing to a potential intra-GOP clash over the matter.

And Trump has relied heavily on acting inspectors general, sometimes for years, to perform functions that often require Senate confirmation. Though he recently nominated a slate of five inspectors general to fill vacant positions permanently, the ranks of more than six-dozen inspectors general are replete with temporary appointments, which gives Trump more direct influence than he would have over Senate-confirmed appointees.

Though Trump’s attacks on these officials have intensified of late, he has long swiped at independent overseers, including Horowitz, who has led two high-profile reviews of the FBI investigations that have in part defined Trump’s presidency: the probe of Hillary Clinton’s handling of classified information and the investigation of the Trump campaign’s interactions with Russia during the 2016 election.

“As bad as the I.G. Report is for the FBI and others, and it is really bad, remember that I.G. Horowitz was appointed by Obama,” Trump said of the inspector general who was confirmed with unanimous support in 2012 and had previously been confirmed to a separate role by the GOP-led Senate in 2003. “There was tremendous bias and guilt exposed, so obvious, but Horowitz couldn’t get himself to say it. Big credibility loss.”

The wide-ranging squeeze on the IG community prompted an unusual pushback from the normally technocratic and muted watchdog community itself. Horowitz, the Justice Department inspector general, lamented Trump’s decision to remove Atkinson for doing his job properly, and he vowed that other IGs would not be dissuaded from “aggressive, independent oversight of the agencies that we oversee.”

Horowitz is due to name a successor to Fine to oversee federal coronavirus relief efforts, though he has asked lawmakers for the power to choose from a broader pool of officials than the law currently allows.

Trump’s recent moves have also prompted outrage from House Democrats, who accused Trump of attempting to erode one of the few functional checks on the mismanagement and abuse in the Executive Branch.

Top House Democrats have proposed measures that would prohibit Trump from removing inspectors general without “good cause.” And some also proposed legislation that would allow Fine to return to the coronavirus oversight role he was initially eyed for.

House Intelligence Committee Chairman Adam Schiff (D-Calif.) has pressed Trump’s acting intelligence community leader, Richard Grenell, for details on whether Atkinson was impeded from conducting any of his investigations before his ouster, as well as a pledge that he wouldn’t exact retaliation against any intelligence officials over perceived disloyalty to Trump.

U.S. Capitol Police briefly shut down the hallway outside Rep. Adam Schiff’s office on Thursday while officers investigated a “suspicious substance.”

The area was cleared approximately one hour after officers set up a yellow tarp in front of the area outside the California Democrat’s office on the second floor of the Rayburn House office building.

Capitol Police spokeswoman Eva Malecki said officials “conducted a thorough investigation and found no hazards.”

Schiff, the House Intelligence Committee chairman and the lead impeachment manager, has received several threats in recent months, and he has been accompanied by a security detail since the beginning of the House’s impeachment inquiry in September. An Arizona man was recently indicted for threatening to kill Schiff.

Shortly after the Senate acquitted President Donald Trump on Wednesday, the White House issued a statement suggesting Schiff should face consequences for leading the impeachment drive. “Will there be no retribution?” press secretary Stephanie Grisham said in a statement. Grisham also indicated Trump would raise the prospect of “payback” for those who crossed him during remarks Thursday.

During her weekly news conference Thursday morning, Speaker Nancy Pelosi said she does not believe the suspicious substance threat against Schiff has anything to do with the White House calling for “retribution.” But she said Trump’s words carry a “ton” of weight and that saying anything threatening is “wrong.”

Melanie Zanona contributed to this report.