WASHINGTON (AP) — Republicans have insisted for months that they have the grounds to launch impeachment proceedings against President Joe Biden. On Thursday, they will begin formally making their case to the public and their skeptical colleagues in the Senate.

The chairmen of Oversight, Judiciary, and Ways and Means will hold the opening hearing of their impeachment inquiry by reviewing the constitutional and legal questions surrounding their investigation of Biden and what they say are links to his son Hunter’s overseas businesses.

“Based on the evidence, Congress has a duty to open an impeachment inquiry into President Biden’s corruption,” Rep. James Comer, the Oversight chairman, said in a statement this week.

Comer added that the committee plans to "present evidence uncovered to date and hear from legal and financial experts about crimes the Bidens may have committed as they brought in millions at the expense of U.S. interests.”

It’s a high-stakes opening act for Republicans as they begin a process that can lead to the ultimate penalty for a president, punishment for what the Constitution describes as “high crimes and misdemeanors.” This is all while they face a resistance in the Senate from Republicans who are worried about the political ramifications of another impeachment — and who say Biden’s conviction and removal from office is a near impossibility.

But House Republicans say they are only investigating and have made no final decision on impeaching the president.

The hearing Thursday will not feature witnesses with information about the Bidens or Hunter Biden's business work. Instead, it will be a soft launch of sorts with testimony from outside experts in tax law, criminal investigations and constitutional legal theory.

Democrats, who decry the investigation as a political ploy aimed at hurting Biden and helping Donald Trump as he runs again for president, said they plan to bring Michael Gerhardt, a law professor who has appeared as expert on two previous impeachment efforts.

In the run-up to the hearing, Republicans were touting a tranche of new documents and bank records that detail wire transfers from a Chinese businessman to Hunter Biden in 2019. Hunter Biden had listed his father’s address on the wire transfer form, which Republicans said provided a clear link to the president.

Abbe Lowell, an attorney for Hunter Biden, said the address on the wire transfer, which he says was a loan, was listed to the president's Delaware home only because it was the address on Hunter Biden's driver's license and "his only permanent address at the time.”

“Once again Rep. Comer peddles lies to support a premise — some wrongdoing by Hunter Biden or his family — that evaporates in thin air the moment facts come out,” Lowell said in a statement.

Republicans have been investigating Hunter Biden for years, since his father was vice president. And while there has been questions raised about the ethics around the family's international business, none of the evidence so far has proven that the president, in his current or previous office, abused his role, accepted bribes or both.

House Republicans are also looking into the Justice Department investigation in Hunter Biden's taxes and gun use that began in 2018. Two IRS whistleblowers came forward to Congress in the spring with claims that department officials thwarted their efforts to fully investigate Hunter Biden and his business dealings and the agents faced retaliation when they pushed back.

The claims have since been disputed by IRS and FBI agents who worked on the case.

The central focus of the testimonies have been surrounding an Oct. 7, 2022 meeting that agents from both the IRS and FBI had with David Weiss, U.S. attorney for Delaware, who has been charged with investigating Hunter Biden.

Gary Shapley, a veteran IRS agent who had been assigned to case, testified to Ways and Means committee in May that Weiss said during that meeting that he was not the “deciding person whether charges are filed” against Hunter Biden.

Two FBI agents who were in attendance told lawmakers this month that they have no recollection of Weiss saying that.

But Republicans have pointed to a failed plea deal over the summer as proof that Hunter Biden received preferential treatment because of who his father was.

Rep. Jason Smith, R-Mo, the chair of the Ways & Means committee, said that their investigation has shown that “Biden family were afforded special treatment that no other American would receive were they not the son of the President of the United States.”

The impeachment inquiry hearing is taking place as the federal government is days away from what is likely to be a damaging government shutdown that would halt paychecks for millions of federal workers and the military.

Democrats say they plan to use the impending fiscal disaster to question Republicans' priorities.

“Three days before they’re set to shut down the United States government, Republicans launch a baseless impeachment drive against President Biden,” Rep. Jamie Raskin, the top Democrat on Oversight, said Wednesday. “No one can figure out the logic of either course of action.”

House Speaker Kevin McCarthy announced the impeachment inquiry this month after he yielded to mounting pressure from his right flank to take action against Biden or risk being ousted from his leadership job.

On Tuesday, McCarthy said the latest bank records showing payments from Chinese individuals to Hunter showed that the president lied during his presidential campaign that no one in his family took money from China.

“President Biden had lied to Americans again,” McCarthy told reporters this week.

The hearing Thursday is expected to be the first of many as House Republicans explore how this inquiry will end and whether or not they have the full support of the conference to bring and pass charges against Biden on the House floor. Regardless, any articles of impeachment would then be sent to the Senate, where Democrats hold a slim 51-49 majority.

“It really comes to how do you prioritize your time?" Sen. John Cornyn, a Republican member of leadership, told The Hill recently. “I don’t know of anybody who believes (Senate Majority Leader) Chuck Schumer will take it up and actually have a trial and convict a sitting president.”